Preoperative Degenerative Changes at the Tibial Sesamoid-Metatarsal Joint in Hallux Valgus: Association With Postoperative Patient-Reported Outcomes After Modified Lapidus Procedure.

Background: Degenerative changes at the sesamoid-metatarsal joints (SMJs) may be a source of pain following hallux valgus surgery. The aims of this study were to describe degenerative changes at the SMJs on weightbearing computed tomography (WBCT) scans and, secondarily, investigate their association with 1-year patient-reported outcome scores following a modified Lapidus procedure for hallux valgus. We hypothesized that reduced joint space in the SMJs would correlate with worse patient-reported outcomes. Methods: Fifty-seven hallux valgus patients who underwent a modified Lapidus procedure had preoperative and minimum 5-month postoperative WBCT scans, and preoperative and at least 1-year postoperative PROMIS physical function (PF), pain interference, and pain intensity scores were included. Degenerative changes at the SMJs were measured using distance mapping between the sesamoids and first metatarsal head on preoperative and postoperative WBCT scans. The minimum and average distances between the first metatarsal head and tibial sesamoid (tibial-SMJ) for each patient preoperatively and postoperatively were measured. Sesamoid station was measured on WBCT scans using a 0 to 3 grading system. Linear regression was used to investigate the correlations between minimum preoperative and postoperative tibial-SMJ distances and 1-year postoperative PROMIS scores. Results: The median minimum and average tibial-SMJ distances increased from 0.82 mm (interquartile range [IQR] 0.40-1.03 mm) and 1.62 mm (IQR 1.37-1.75 mm) preoperative to 1.09 mm (IQR 0.96-1.23 mm) and 1.73 mm (IQR 1.60-1.91 mm) postoperative (P < .001 and P < .001), respectively. In a subset of patients with complete sesamoid reduction, we found an association between preoperative minimum tibial-SMJ distance and 1-year postoperative PROMIS PF scores (coefficient 7.2, P = .02). Conclusion: Following the modified Lapidus procedure, there was a statistically significant increase in the tibial-SMJ distance. Additionally, in patients with reduced sesamoids postoperatively, reduced preoperative tibial-SMJ distance correlated with worse PROMIS PF scores. Level of Evidence: Level IV, case series.

Midterm outcomes of the modified Lapidus arthrodesis using the Phantom® Intramedullary Nail System for the treatment of hallux valgus.

BACKGROUND: Lapidus arthrodesis is one of the most commonly used techniques in the correction of moderate and severe hallux valgus. We analyzed the clinical and radiological outcomes after using the Phantom® Lapidus intramedullary nail to find an effective technique with low complications. METHODS: We retrospectively analyzed data of 52 patients who underwent a modified Lapidus arthrodesis with an intramedullary nail at our center from November 2019 to September 2022. The mean follow-up period was 27 (range, 18-34) months. Clinical results were evaluated using the visual analog scale (VAS), the European Foot and Ankle Society score (EFAS) and the American Orthopaedic Foot and Ankle Society score (AOFAS); three different radiological measures were analyzed. RESULTS: The mean AOFAS score increased from 44.8 to 82 points. The mean EFAS score increased from 11.2 to 20.1 points. The mean VAS score decreased by 4.7 points. The mean EFAS Sport score was increased from 9.2 (SD 4.6) to 12.6 (SD 5.4) points. The intermetatarsal angle decreased from 15° to 6.9° and the hallux valgus angle by a mean of 17.9°. The forefoot width reduced from 93.6 to 84.7 mm. All results were statistically significant (p < .001). One case of nonunion was recorded. No implant-related complications were observed. CONCLUSIONS: This device was effective in correcting moderate to severe hallux valgus, with significant patient satisfaction. Its complication rate was not higher than that of other fixation devices. Correct compression of the arthrodesis, absence of extraosseous material, and multidirectional stability are important qualities of this implant for the correct treatment of this pathology. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Cannulated screws versus nitinol staple for tarsometatarsal fusion: A cadaveric biomechanical comparison model.

BACKGROUND: The objective of this study was to evaluate the biomechanical stability of a medially placed nitinol staple compared to two crossed-screws in the first TMT-1 joint fusion in a cadaveric cyclic loading model. METHODS: Seven matched pairs (N = 7) of lower limb cadaveric specimens were utilized. TMT-1 joints from each donor were fixed with a medially placed nitinol staple or dorsally placed two 3.5 mm partially threaded cannulated crossed-screws. Specimens were tested in a 4-point bending setting with increasing cyclic forces. RESULTS: The mean plantar gapping was not significantly different between the two groups at any loading stage below 200 N. Specimens fixed with a nitinol staple failed at a mean load of 305 ± 57 N. Conversely, those fixed with crossed-screws failed at 373 ± 86 N. (P = .09). CONCLUSION: There was no statistical difference between a medially placed nitinol staple and dorsally placed crossed-screws in failure loads and plantar gapping under cyclic loads at the TMT-1 joint, however, the staple fixation was much more variable. LEVEL OF EVIDENCE: Level V, basic science study, biomechanics.

Correlation of Clinical Outcomes and Relative Position of the First Metatarsal After the Modified Lapidus Procedure.

BACKGROUND: Hallux valgus is a complex 3-dimensional deformity, and the modified Lapidus is a commonly used procedure to correct moderate to severe cases. Shortening and elevation of the first ray can occur with this procedure, which may result in increased pressure on the lesser metatarsal heads. However, there is currently no consensus regarding an accepted length and elevation of the first ray following the modified Lapidus. Therefore, the purpose of this study is to evaluate the impact of the position of the first ray on patient-reported outcome measures. METHODS: This retrospective study identified 68 patients (72 feet) who underwent the modified Lapidus bunionectomy over a 4-year period at a single institution with a median follow-up of 24 months (range, 11-35.6 months). Patients were included if they were over 18 years of age, had pre- and postoperative weightbearing computed tomography (WBCT) scans, and preoperative and minimum 1-year postoperative Patient-Reported Outcome Measurement Information System (PROMIS) scores. PROMIS scores from 6 domains including physical function, pain interference, pain intensity, global physical health, global mental health, and depression were evaluated and compared pre- and postoperatively. Radiographic parameters were measured and compared before and after surgery. Paired t tests were used to evaluate the significance of pre- to postoperative changes. Differences between cohorts were compared using Mann-Whitney U test for continuous variables or Fisher exact test for categorical variables. Correlation between radiographic measurements and patient-reported outcomes were assessed using the Spearman rank rho estimate and visualized with scatterplots with a linear regression. RESULTS: PROMIS physical function, pain interference, pain intensity, and global physical health improved significantly following the modified Lapidus (all P < .001); however, scores did not show any significant correlation with shortening of the first ray up to a maximum shortening of 4.8 mm. The length of the first metatarsal relative to the second decreased by an average of 2.7 mm following the procedure when measured on WBCT (P < .001), and 2.6 mm when measured on plain radiographs (P < .001). No significant elevation of the first ray was observed postoperatively. CONCLUSION: This study revealed that the Lapidus bunionectomy resulted in significantly improved pain and physical function at short-term follow-up. The amount of first ray shortening and elevation that occurred in this cohort did not adversely affect patient-reported outcomes.

Correction method for moderate and severe degrees of hallux valgus associated with transfer metatarsalgia.

BACKGROUND: Hallux valgus (HV) is a common foot deformity that manifests with increasing age, especially in women. The associated foot pain causes impaired gait and decreases quality of life. Moderate and severe HV is a deformity that is characterized by the involvement of lesser rays and requires complex surgical treatment. In this study, we attempted to develop a procedure for this condition. AIM: To analyse the treatment results of patients who underwent simultaneous surgical correction of all parts of a static forefoot deformity. METHODS: We conducted a prospective clinical trial between 2016 and 2021 in which 30 feet with moderate or severe HV associated with Tailor's bunion and metatarsalgia were surgically treated via a new method involving surgical correction of all associated problems. This method included a modified Lapidus procedure, M2M3 tarsometatarsal arthrodesis, intermetatarsal fusion of the M4 and M5 bases, and the use of an original external fixation apparatus to enhance correction power. Preoperative, postoperative, and final follow-up radiographic data and American Orthopaedic Foot and Ankle Society (AOFAS) scores were compared, and P values < 0.05 were considered to indicate statistical significance. RESULTS: The study included 28 females (93.3%) and 2 males feet (6.7%), 20 (66.7%) of whom had a moderate degree of HV and 10 (33.3%) of whom had severe deformity. M2 and M3 metatarsalgia was observed in 21 feet, and 9 feet experienced pain only at M2. The mean follow-up duration was 11 months. All patients had good correction of the HV angle [preoperative median, 36.5 degrees, interquartile range (IQR): 30-45; postoperative median, 10 degrees, IQR: 8.8-10; follow-up median, 11.5 degrees, IQR: 10-14; P < 0.01]. At follow-up, metatarsalgia was resolved in most patients (30 vs 5). There was a clinically negligible decrease in the corrected angles at the final follow-up, and the overall AOFAS score was significantly better (median, 65 points, IQR: 53.8-70; vs 80 points, IQR: 75-85; P < 0.01). CONCLUSION: The developed method showed good sustainability of correction power in a small sample of patients at the one-year follow-up. Randomized clinical trials with larger samples, as well as long-term outcome assessments, are needed in the future.

Lapidus Arthrodesis for Correction of Hallux Valgus Deformity: A Systematic Review and Meta-Analysis.

BACKGROUND: The aim of this study was to evaluate and compare different fixation methods to achieve Tarsometatarsal joint I (TMT-1) arthrodesis in patients with hallux valgus regarding radiographic correction, complication profile, and clinical outcomes. METHODS: A systematic review and meta-analysis included primary literature results of evidence level 1 to 3 studies in German and English. Inclusion and exclusion criteria were established and applied, along with parameters suitable for comparison of data. RESULTS: 16 studies with a total of 1176 participants met the inclusion criteria for this analysis. Twelve evaluation criteria were compared among 3 fixation techniques; comprised of a screw-only, dorsomedial plating- and plantar plating cohort. There was no statistical difference in deformity correction (both intermetatarsal- and hallux valgus angle), or AOFAS score between the cohorts. The complication rate was 13% in the plantar-, 19.5% in the dorsomedial-, and 24.5% in the screw cohort. Nonunion was seen in 0.7% of participants in the plantar, 1.4% in the dorsomedial, and 5.3% in the screw group. The time until complete weightbearing correlated positively with the development of nonunion, with a coefficient of 0.376 (P = .009). Hardware removal was performed in 11.8% of patients in the dorsomedial cohort, 7.7% in the screw cohort, and 3.6% in the plantar cohort. CONCLUSION: Based on the results of meta-analysis of heterogeneous studies, plantar plating facilitated early weightbearing and patient mobilization compared to the other fixation methods, while carrying the lowest nonunion, hardware removal, and general complication risk. However, owing to the relatively small number of patients in the plantar plating group, more work is necessary to elucidate the benefits of plantar plating for a first tarsometatarsal joint arthrodesis. Development of complications appears to be largely dependent on the fixation model, rather than patient mobilization alone.Level of Evidence: 3.

Operative Time, Cost, and Union Rate of Power Rasp Joint Preparation Versus Traditional Preparation in Arthrodesis of the Foot and Rearfoot.

Time spent in the operating room is valuable to both surgeons and patients. One of the biggest rate-limiting factors when it comes to arthrodesis procedures of the foot and ankle is cartilage removal and joint preparation. Power instrumentation in joint preparation provides an avenue to decrease joint preparation time, thus decreasing operating room time and costs. Arthrodesis of 47 joints (n) from 27 patients were included. Power rasp joint preparation in 26 joints was compared to traditional osteotome and curette joint preparation in 21 joints in both time (seconds), cost (total operating room time cost per minute), and union rate. The overall mean joint preparation time using power rasp for the subtalar joint was 268.3 seconds, talonavicular joint 212.3 seconds, calcaneocuboid joint 142.6 seconds, 1st TMT 107.2 seconds. Mean joint preparation time using traditional method for subtalar joint 509.8 seconds, talonavicular joint 393.0 seconds, calcaneocuboid joint 400.0 seconds, 1st TMT 319.6 seconds. Mean cost of joint preparation using power rasp for subtalar joint $165.47, talonavicular joint $130.89, calcaneocuboid joint $87.94, 1st TMT $66.11. Mean cost of joint preparation using traditional techniques for subtalar joint $314.34, talonavicular joint $242.35, calcaneocuboid joint $246.67, 1st TMT $197.33. Overall union rate was 98% (1 asymptomatic non-union). Increasing efficiency in the operating room is vital to every surgeon's practice. Power rasp joint preparation is a viable option to increase efficiency and decrease operative time, this study shows no statistically significant differences in union rate, with comparable rates to existing literature.

First tarsometatarsal arthrodesis for severe hallux valgus using the tension band principle - Technical tip and case series.

BACKGROUND: Hallux valgus (HV) is a common foot pathology. Severe HV in the presence of Tarsometatarsal joint (TMTJ) instability is often managed with arthrodesis of the 1st TMTJ. There are concerns regarding non-union and malunion (particularly the early loss of inter-metatarsal angle correction before complete arthrodesis). We report our medium-term results of a small series of patients that underwent an evolved surgical technique utilising orthogonal staples and a transverse suture button fixation to address biomechanical concerns with traditional Lapidus arthrodesis. METHODS: A retrospective study of a consecutive series of patients who underwent this surgical technique between February 2017 and May 2022. Clinical outcomes were validated through Patient-reported outcomes measures (PROMS); EuroQol-5 Dimension (EQ-5D) and Manchester-Oxford Foot Questionnaires (MOXFQ). Radiographic parameters (hallux valgus (HVA), intermetatarsal (IMA), distal metatarsal articular angle (DMAA)) were assessed. Union of the arthrodesis and complications were recorded. RESULTS: During the study period, 9 feet underwent the procedure. Radiographic data was available for all nine and PROMS data for seven (77.8%). Significant improvement occurred in all radiographic deformity parameters at mean 6-month follow-up. Mean ± standard deviation correction calculated preoperatively as HVA 40.2°, IMA 19.3° and DMAA 15.8°, corrected to HVA 15.4°, IMA 5.8° and DMAA 5.9° postoperatively. (HVA; P < 0.001, IMA; P < 0.001, DMAA; P < 0.001) Clinical PROMs at mean follow-up of 2 years were MOXFQ 34.4 ± 25.2, EQ-5D-5 L 0.819 ± 0.150 and VAS pain 13.6 ± 13.6. There were no cases of non-union, Tibialis anterior tendon irritation or hallux varus. Complications included first MTPJ stiffness in one case and CRPS and dorsiflexion malunion of the first ray in another patient. CONCLUSION: This preliminary study of the procedure used in this series confirm this is a safe surgical technique to address severe HV with a low rate of non-union and significant radiographic improvements. A larger patient dataset is needed to evaluate this procedure robustly.

Is there a tolerance for extension of the first metatarsal after the Lapidus procedure? A clinical, functional, and hindfoot radiographic analysis.

PURPOSE: Based on the tripod concept of load distribution, our study aimed to evaluate whether a slight extension of first metatarsal (M1) that may occur after the Lapidus procedure (LP) could alter the radiographic measurements of the hindfoot and influence clinical and functional outcomes. METHODS: Twenty-five patients (27 feet) were reviewed. Hindfoot radiographic analysis was based on seven measurements. Clinical and functional outcomes were evaluated with self-reported questionnaires. Transfer metatarsalgia was also assessed. Correlation analysis was performed according to variations of the studied variables. RESULTS: The average extension of the M1 was 4.26 degrees (p < 0.001). None of the hindfoot radiographic measurements changed significantly (p = 0.13, p = 0.50, p = 0.19, p = 0.70, p = 0.11, p = 0.36, p = 0.83). Patients improved on most questionnaires (p < 0.001). None presented transfer metatarsalgia. No correlation between M1 extension and clinical and functional outcomes was found. CONCLUSION: Possibly there is a tolerance of M1 extension in which it does not alter the radiographic measurements of the hindfoot, overload the lesser metatarsals, or compromise clinical and functional outcomes.

The Triplanar Hallux Abducto Valgus Classification System: Is it Valid?

Historically, 2-dimensional radiographic study techniques have been used to classify deformity and guide treatment of hallux valgus deformities in the transverse plane. Recently, a triplanar hallux abducto valgus classification system was proposed. The key elements of this classification system are the pathologic alignments in 3 anatomic planes. The triplanar hallux abducto valgus classification system is intended to clarify the deformity and apply a triplanar anatomic algorithm for treatment. To our knowledge, this classification system has not been validated. Our objective was to assess reliability of the triplanar hallux valgus classification system. Patients with hallux abducto valgus were identified from a foot and ankle registry. Digital radiographs were assembled in a digital slide presentation. The eligibility criteria required complete radiographic studies and represented varying degrees of hallux abducto valgus. The reviewers included 3 board-certified, fellowship-trained orthopedic foot and ankle surgeons. Each reviewer independently classified the hallux abducto valgus deformity for a total of 75 observations. After an 8-week washout period, the order of the hallux abducto valgus cases was randomized in the digital slide presentation and redistributed to the reviewers. The average kappa value from 3 readers was 0.241 with 95% CI (0.093-0.374), indicating a fair agreement. The inter-reader agreement was 0.046 with 95% CI (-0.041 to 0.112), showing poor agreement between readers. Our results indicate the triplanar hallux abducto valgus is not a reliable classification system. While this is the first known triplanar hallux abducto valgus classification system, it lacks prognostic value and reliability.

Open vs Minimally Invasive Resection of the First Metatarsocuneiform Joint: An Anatomical Study.

BACKGROUND: The modified Lapidus arthrodesis is a standard procedure to correct middle to severe hallux valgus (HV) deformities. Recently, minimally invasive techniques of first metatarsocuneiform joint (MCJ) resection using a Shannon burr were described. The primary goal of this study is to compare the anatomical efficacy and safety of first MCJ resection using a straight 2 × 13-mm Shannon burr and minimally invasive technique (MIS) vs an open technique using an oscillating saw. METHODS: Ten pairs of fresh frozen cadaveric feet were randomly assigned to open or MIS first MCJ resection with subsequent systematic dissection. For the MIS procedure, a dorsomedial approach was used and for the open procedure a medioplantar approach was used. Cartilage removal was investigated by analyzing standardized scaled photographs of the resected articular surfaces with ImageJ software. Nearby structures at risk were analyzed for iatrogenic violation: tibialis anterior (TA), extensor hallucis longus (EHL) and peroneus longus (PL) tendons, and the Lisfranc ligament complex (LLC). RESULTS: In the MIS group, the median cartilage resection was 85.9% at the cuneiform and 85.6% at the metatarsal bone compared to 100% cartilage resection in open technique (P < .01). Iatrogenic damage of the LLC, EHL, and TA tendons was not found in any group. The PL tendon was thinned out (<25% of tendon thickness) in 4 cases (40%) in the open group and in 1 case (10%) in the MIS group. A safe zone of 3.0 mm between the articular surface of the cuneiform bone and the LLC was identified, which can be resected without putting the LLC at risk when performing lateral-based wedge resections. CONCLUSION: In this cadaver study with the procedures performed by an experienced foot and ankle surgeon, and using 2 different surgical approaches, we found general parity between the Shannon burr MIS technique vs oscillating saw open technique techniques with more risk to the PL with our open technique and approximately 15% less cartilage resection with our MIS technique. LEVEL OF EVIDENCE: Level V, cadaver study.

Radiographic and Patient-Reported Outcomes of a Low-Cost Modified Lapidus Bunion Correction Technique.

Background: The modified Lapidus (ML) is a powerful procedure for correction of hallux valgus (HV) with emerging techniques. Studies considering patient-reported outcomes, radiographic measures, complications, and implant costs are currently limited. Methods: Retrospective cohort with prospectively collected Patient Reported Outcome Information System Physical Function (PROMIS-PF) Computerized Adaptive Test (CAT) scores, radiographic parameters (intermetatarsal angle, IMA; hallux valgus angle, HVA; and tibial sesamoid position, TSP), complications, and total operative time and implant costs were reviewed from 2014 to 2019. Results: Seventy-three feet (68 patients) underwent bunion correction by ML with lag-screw fixation. Median age was 55.8 years (IQR 45.6, 53.9), 4 of 73 (5.5%) were male, 11 of 73 (15.1%) were smokers, and 15 of 73 (20.6%) were diabetic (median HbA1c 6.4% [IQR 6.0, 7.4], none insulin dependent, 5 of 15 with neuropathy). Complications included 6 of 73 (8.2%) wound issues resolved with topical or oral treatment, 9 of 73 (12.3%) painful or broken hardware requiring hardware removal. Two of 73 (2.7%) had persistent pain despite union. One of 73 (1.4%) was overcorrected and required first MTP arthrodesis. Of 3 nonunions (2.7%), 1 resolved with corrected hypothyroidism, 1 was asymptomatic and required no treatment, 1 had a hallux valgus recurrence and sought revision surgery elsewhere. Preoperative radiographic angles were HVA 35 degrees, IMA 14 degrees which improved at final postoperative follow up to HVA 10 degrees, IMA 6 degrees. Tibial sesamoid position improved from 6.05 ± 1.00 to 2.22 ± 1.38. Thirty-two patients had preoperative and 42 had 1-year postoperative outcomes. PROMIS-PF (51% collection rate) was 43 (IQR 37,52) preoperatively, 37 (31, 39) at 6 weeks, 46 (42, 51) at 3 months, and 49 (41, 53) at >360 days postoperatively. The drop in PROMIS-PF between preoperative and 6 weeks and the rise from 6 weeks to 3 months were statistically significant. Pre- and postoperative PROMIS-PF scores were not significantly different. Implant cost averaged US$146. Discussion/Conclusion: We report low complication rates and costs with high patient postoperative functional and radiographic outcomes. PROMIS-PF decreased acutely postoperatively but recovered and maintained high levels by 3 months postoperatively. Level of Evidence: Level IV, case series.

Multiple factors contributing to the metatarsal head eversion in hallux valgus deformity. A prospective study using weight-bearing CT.

PURPOSE: Recently first tarsometatarsal arthrodesis for hallux abducto valgus (HAV) has been advocated as the sole procedure to correct the multiplanar components of the deformity. However, recent debate suggests other factors such as rearfoot pronation and metatarsal torsion affect frontal plane metatarsal eversion and sesamoid positioning. Using weight-bearing CT, 12 feet (12 subjects) with HAV deformities were placed in positions of maximum rearfoot pronation and supination in order to study the effects on metatarsal eversion, sesamoid rotation/displacement, and secondarily the influence of first metatarsal torsion. Sesamoid displacement was quantified by the novel use of the sesamoid displacement angle. PRINCIPLE RESULTS: Although first metatarsal eversion was nearly double in the pronated versus supinated foot, the difference was not statistically significant. Therefore, the bulk of first metatarsal eversion was not secondary to rearfoot eversion. Conversely, a significant positive correlation was found between metatarsal torsion and metatarsal head eversion angles in both supinated and pronated foot positions, with the strongest correlation with rearfoot pronation. Finally, significant increases in sesamoid displacement angles were noted with pronation. MAJOR CONCLUSIONS: The findings of the present study support the contention that multiple factors are associated with frontal plane first metatarsal eversion and sesamoid displacement. Weight-bearing CT scanning can be used to effectively evaluate the frontal plane components in HAV deformities. The sesamoid displacement angle appears to be a useful adjunct to evaluating the hallucal sesamoids. For surgical correction of the deformity, consideration should be given to pre-operative weight-bearing CT evaluation of the foot. This can illuminate the effects of rearfoot/medial column pronation and the potential influence of metatarsal torsion on the frontal plane components of this triplane deformity. In this way the potential for post-operative HAV recurrence can be minimized.

Changes in Radiographic Alignment Following Metatarsophalangeal Fusion, Distal Metatarsal Osteotomy, and Lapidus.

BACKGROUND: The purpose of this study is to evaluate the effect of the different surgical treatments for hallux valgus on various radiographic measures of bunion correction. METHODS: A retrospective cohort study was conducted at a single academic medical center involving 2 fellowship-trained foot and ankle surgeons. One hundred and nineteen feet (110 patients) were included. Procedures included first metatarsophalangeal (MTP) arthrodesis (n = 88), Chevron and/or Scarf osteotomy (n = 23), and Lapidus (n = 8). Overall, 78.2% of patients were female, mean age was 60.49 (range, 16-81) years, and mean follow-up was 1.20 (range, 0.25-3.92) years. RESULTS: Hallux valgus angle (HVA) significantly differed preoperatively (MTP = 33.33°, Chevron/Scarf = 27.03°, Lapidus = 32.56°; P = .026). There was no difference in distal metatarsal articular angle (DMAA) preoperatively (MTP = 18.87°, Chevron/Scarf = 17.80°, Lapidus = 14.39°; P = .629). At final follow-up, DMAA was significantly greatest among the Lapidus bunionectomy cohort (MTP = 9.63°, Chevron/Scarf = 13.51°, Lapidus = 17.45°; P = .005). There was no difference in infection (MTP = 6.8%, Chevron/Scarf = 4.4%, Lapidus = 0.0%; P = 1.00) or reoperation (MTP = 19.3%, Chevron/Scarf = 21.7%, Lapidus = 12.5%; P = .921) rates between cohorts, although both rates were highest in the first MTP arthrodesis group. CONCLUSION: Among the 3 hallux valgus corrections studied, Lapidus bunionectomy fared the worst regarding DMAA correction at first follow-up and final follow-up, compared with MTP fusion and distal metatarsal osteotomies. Other radiographic measures showed no significant difference among the groups. LEVEL OF EVIDENCE: Level III: Retrospective cohort study.

Indications and possible limitations using medio-plantar plate systems in tarsometatarsal 1 fusions - A cadaveric study.

BACKGROUND: The tarsometatarsal 1 arthrodesis is an adequate treatment for moderate to severe hallux valgus deformity and instability of the first ray. Plantar plating arthrodesis has been shown to provide better mechanical stability and fewer postoperative complications than screw fixation or medial plating. The medio-plantar plate is a new plate design for Lapidus arthrodesis. It could combine the biomechanical advantages of the plantar plate and the anatomical overview of a medial plate. However, the implanted material can cause irritation of the tibialis anterior, which in some cases may require removal of the material. The purpose of this study was to examine the possibility of tendon irritation following medio-plantar first tarsometatarsal joint arthrodesis using cadaveric specimens. METHODS: The study involved the simulated surgical procedure of medio-plantar plate arthrodesis on 30 lower extremities. After the plates were fixed, a thorough examination of the feet was conducted to assess any tendon irritation and to determine a recommendation for placement of the medio-plantar plate based on the Olewnik classification. RESULTS: Irritation of the tibialis anterior tendon components with the medio-plantar plate depends mainly on the anatomic norm variant, classified according to Olewnik et al. A medio-plantar plate is particularly recommended in TA tendon Olewnik type 3 and type 5. The positioning of a medio-plantar plate in Olewnik type 1 and type 2 tendons depends on the anatomic fit of the medio-plantar plate and the bony configuration of the TMT 1 joint. A large portion of the TA tendon must be detached, so a different plate design may be preferred in these patients. CONCLUSIONS: TMT 1 arthrodesis with medio-plantar plating of the first tarsometatarsal joint should be performed considering the anatomic TA tendon variations. LEVEL OF EVIDENCE: Level V, Expert Opinion includes Case Reports and Technique Tips.

A comparative analysis of clinical, functional and radiographic outcomes of patients with and without fusion between the first and second metatarsals after the lapidus procedure.

BACKGROUND: The aim of this study was to compare the clinical, functional and radiographic outcomes in patients who underwent the original Lapidus procedure (OLP) with fusion and undesired non-fusion between the first (M1) and second (M2) metatarsals. METHODS: A retrospective and comparative analysis of 29 patients (38 feet) who underwent the OLP was performed. They were divided in two groups: (1) 23 feet in which fusion occurred and (2) 15 with undesired non-fusion. Clinical and functional data were assessed with the VAS for pain, AOFAS, LEFS and SF-12. SF-12 comprises physical and mental health scales (PCS-12 and MCS-12). Radiographic parameters assessed were bony and soft tissue forefoot widths (BSFW), intermetatarsal-angle (IMA) and HV-angle (HVA). RESULTS: Separately, the groups presented significant improvements in all questionnaires (p < 0.001), except on MCS-12 (fusion p = 0.08 and non-fusion p = 0.27). When comparing both groups, patients with fusion had higher AOFAS scores (p < 0.05). Both groups presented the same improvements on BSFW, IMA and HVA (p = 0.09, p = 0.16, p = 0.52 and p = 0.63). CONCLUSION: Excellent results were observed, even when without fusion between M1 and M2. Patients who evolved with fusion between the M1 and M2 showed greater improvements in the AOFAS score. LEVEL OF EVIDENCE: III, retrospective comparative study.

Biomechanical Evaluation of Fourth Generation Minimally Invasive Distal First Metatarsal Osteotomy-Akin Osteotomy Technique on First Ray Articular Contact Properties.

BACKGROUND: Hallux valgus is a common deformity encountered but remains a complex clinical entity. Fourth-generation minimally invasive surgery (MIS) techniques consisting of a percutaneous distal metatarsal transverse osteotomy combined with an Akin osteotomy have been used to address mild to severe hallux valgus deformities. The benefits of an MIS approach include improved cosmesis, faster recovery, lower opiate requirement, immediate weightbearing, and favorable outcomes relative to a traditional, open procedure. An understudied area with respect to hallux valgus correction is the effect that osteotomies can have on the articular contact properties of the first ray following correction. METHODS: Sixteen paired cadaveric specimens were dissected to include the first ray and tested in a customized apparatus. Specimens were randomized to receive a distal transverse osteotomy translated either 50% or 100% of the width of the first metatarsal shaft. The osteotomy was performed with either a 0° or 20° distal angulation of the burr relative to the shaft in the axial plane. Specimens were tested in the intact state and following the distal first metatarsal osteotomy for peak pressure, contact area, contact force and center of pressure at the first metatarsophalangeal (MTP) and first tarsometatarsal (TMT) joints. An Akin osteotomy was then performed on each specimen, and peak pressure, contact area, contact force, and center of pressure were recalculated. RESULTS: There was a notable decrease in peak pressure, contact area, and contact force across the TMT joint with greater shifts of the capital fragment. However, at 100% translation of the capital fragment, distal angulation of the osteotomy by 20° appears to improve loading across the TMT joint. Addition of the Akin osteotomy at 100% translation also aids in increasing the contact force across the TMT joint. The MTP joint is less sensitive to changes in shifts and angulation of the capital fragment. The Akin osteotomy also leads to increased contact force across the MTP joint when the capital fragment is translated 100%. CONCLUSION: While the clinical significance is unknown, larger shifts of the capital fragment lead to greater load alterations at the level of the TMT joint than the MTP joint. Distal angulation of the capital fragment and the addition of an Akin osteotomy can aid in reducing the size of those changes. The Akin can lead to increased contact forces at the MTP joint with 100% translation of the capital fragment. LEVEL OF EVIDENCE: Not applicable, Biomechanical study.

Biomechanical Comparison of Medio-Plantar and Plantar Plate Fixation for First Tarsometatarsal Joint Arthrodesis.

Plantar plate positioning has been demonstrated as biomechanically superior. However, some operators remain resentful about the morbidity of the surgical approach. To provide improved plate fixation for first tarsometatarsal joint arthrodesis with respect to the tibialis anterior tendon, a medio-plantar plate was developed. The purpose of this biomechanical study was to compare its construct stability to that of a plantar plate construct. Twelve pairs of fresh frozen human specimens were used in a matched pair test. Each pair was fixed with a 4 mm compression screw and either a plantar locking plate or a medio-plantar locking plate. A cantilever beam test was performed in dorsiflexion. Before and after cyclic loading (5000 cycles; 40 N), bending stiffness and relative movements at the joint space were monitored in a quasi-static test including optical motion tracking. Maximum load and bending moment to failure were investigated in a load-to-failure ramp test. The bending stiffness of both groups did not significantly differ before (plantar 49.9 N/mm ± 19.2; medio-plantar 53.9 N/mm ± 25.4, p = 0.43) or after (plantar 24.4 N/mm ± 9.7; medio-plantar 35.3 N/mm ± 22.0, p = 0.08) cyclic loading but decreased significantly in both groups (p < 0.01) after cyclic loading. Relative movement increased significantly during cyclic testing in both groups (p < 0.01) but did not differ significantly between the groups before (p = 0.29) or after (p = 0.16) cyclic loading. Neither load nor bending moment to failure were significantly different (plantar 225 N ± 78, 10.8 Nm; medio-plantar 210 N ± 86, 10.1 Nm, p = 0.61). Both plate constructs provided equivalent construct stability, both being well suited for Lapidus arthrodesis.

First Metatarsal Rotation After Scarf Osteotomy for Hallux Valgus.

BACKGROUND: Recurrence after surgical correction of hallux valgus may be related to coronal rotation of the first metatarsal. The scarf osteotomy is a commonly used procedure for correcting hallux valgus but has limited ability to correct rotation. Using weight-bearing computed tomography (WBCT), we aimed to measure the coronal rotation of the first metatarsal before and after a scarf osteotomy, and correlate these to clinical outcome scores. METHODS: We retrospectively analyzed 16 feet (15 patients) who had a WBCT before and after scarf osteotomy for hallux valgus correction. On both scans, hallux valgus angle (HVA), intermetatarsal angle (IMA), and anteroposterior/lateral talus-first metatarsal angle were measured using digitally reconstructed radiographs. Metatarsal pronation angle (MPA), alpha angle, sesamoid rotation angle, and sesamoid position were measured on standardized coronal WBCT slices. Preoperative and postoperative (12 mo) clinical outcome scores (Manchester Oxford Foot Questionnaire and Visual Analogue Scores) were captured. RESULTS: Mean HVA was 28.6 ± 10.1° preoperatively and 12.1 ± 7.7° postoperatively (P < .001). Mean IMA was 13.7 ± 3.8° preoperatively and 7.5 ± 3.0° postoperatively (P < .001). Before and after surgery, there were no significant differences in MPA (11.4 ± 7.7 and 11.4 ± 9.9°, respectively; P = .75) or alpha angle (10.9 ± 8.0 and 10.7 ± 13.1°, respectively; P = .83). There were significant improvements in sesamoid rotation angle (SRA) (26.4 ± 10.2 and 15.7 ± 10.2°, respectively; P = .03) and sesamoid position (1.4 ± 1.0 and 0.6 ± 0.6, respectively; P = .04) after a scarf osteotomy. There were significant improvements in all outcome scores after surgery. Poorer outcome scores correlated with greater postoperative MPA and alpha angles (r = .76 (P = .02) and .67 (P = .03), respectively). CONCLUSION: A scarf osteotomy does not correct first metatarsal coronal rotation, and worse outcomes are linked to greater postoperative metatarsal rotation. Rotation of the metatarsal needs to be measured and considered when planning hallux valgus surgery. Further work was needed to compare postoperative outcomes with rotational osteotomies and modified Lapidus procedures when addressing rotation.Level of Evidence: 4.

Radiographic Evaluation of First Tarsometatarsal Joint Arthrodesis for Hallux Valgus Deformity: Does the Fusion of the First to the Second Metatarsal Base Reduce the Radiological Recurrence Rate?

BACKGROUND: Modified Lapidus arthrodesis (MLA) is a well-established treatment option for symptomatic hallux valgus deformity (HVD). However, recurrence of the deformity remains a concern. The goal of this study was to evaluate the effect of an additional intermetatarsal fusion on the radiographic recurrence rate after first tarsometatarsal (TMT-I) arthrodesis. METHODS: This is a retrospective evaluation of 56 feet that underwent TMT-I arthrodesis for moderate to severe HVD. Twenty-three feet received an isolated arthrodesis of the TMT-I joint (TMT-I), whereas 33 feet received an additional fusion between the base of the first and the second metatarsal bone (TMT-I/II). Various radiological parameters were determined preoperatively, 6 weeks and at a mean of 2 years postoperatively. RESULTS: The intermetatarsal angle (IMA) and the hallux valgus angle (HVA) were significantly lowered at both follow-up evaluations in both groups. In the TMT-I/II group, the initial reduction of HVA was significantly higher (29.3° vs 21.1°). This difference disappeared by the second follow-up, leaving no significant differences between both techniques at final follow-up. Radiological recurrence rates of HVD were comparable in both groups. CONCLUSIONS: Isolated TMT-I arthrodesis provides reliable radiological results in the correction of HVD. Whether additional fusion of the first and second metatarsal base should be routinely performed remains unclear. LEVELS OF EVIDENCE: Level 3.