Distal Chevron Osteotomy Increases Anatomic Intermetatarsal Angle in Hallux Valgus.

BACKGROUND: Distal chevron metatarsal osteotomy (DCO) is a common technique to address hallux valgus (HV), which involves coronal translation of the capital fragment resulting in a nonanatomic first metatarsal. The purpose of this study was to evaluate the radiographic effect of the DCO on the anatomic vs the mechanical axis of the first metatarsal. Our hypothesis was that patients undergoing DCO would have improvement in the mechanical metatarsal axis but worsening of the anatomic axis. METHODS: This was a retrospective case series of consecutive patients who underwent DCO for HV. The primary outcomes were the change in anatomic first-second intermetatarsal angle (a1-2IMA) vs mechanical first-second intermetatarsal angle (m1-2IMA). Secondary outcomes included the change in hallux valgus angle (HVA) and medial sesamoid position. RESULTS: 40 feet were analyzed with a mean follow-up of 21.2 weeks. The a1-2IMA increased significantly (mean, 4.1 degrees) whereas the m1-2IMA decreased significantly (mean, 4.6 degrees) following DCO. There was a significant improvement in HVA (mean, 12.5 degrees). Medial sesamoid position was improved in 21 feet (52.5%). Patients with no improvement in sesamoid position were found to have a larger increase in a1-2IMA (mean, 4.7 vs 3.5 degrees, P = .03) and less improvement in m1-2IMA (mean, 3.8 vs 5.2 degrees, P = .02) compared to patients with improvement in sesamoid position. CONCLUSION: Distal chevron osteotomy for HV was associated with worsening of the anatomic axis of the first metatarsal despite improvements in the mechanical metatarsal axis, HVA, and medial sesamoid position. Greater worsening of the anatomic axis was associated with less improvement of sesamoid position. Our findings may suggest the presence of intermetatarsal instability, which could limit the power of DCO in HV correction for more severe deformities and provide a mechanism for HV recurrence. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Analysis of Orthopaedic Job Availability in the United States Based on Subspecialty.

BACKGROUND: The number of orthopaedic residency graduates pursuing additional subspecialty training has increased along with the percentage of advertised jobs requiring fellowship. As such, the implications of fellowship training on job availability and marketability may impact their choice of subspecialty. The purpose of this study was to evaluate job availability in the United States for general orthopaedics and orthopaedic subspecialties. METHODS: Job advertisements in 2019 were reviewed from the career center databases of the Journal of Bone and Joint Surgery, American Academy of Orthopaedic Surgeons, as well as of individual subspecialty societies. Job listings were cross referenced to identify unique jobs within the United States, which were categorized by the orthopaedic training required, practice type, and location. To assess job availability, a ratio of fellows to job listings was calculated based on the number of matched candidates for nine subspecialty fellowships and the number of residency graduates entering general practice in 2019. RESULTS: A total of 466 unique job listings were identified with 114 generalist and 352 subspecialist positions. The subspecialties with the lowest number of fellows per advertised job were foot and ankle (1.1), adult reconstruction (2.0), and trauma (2.1). The subspecialties with the highest number of fellows per advertised job were sports medicine (6.3), shoulder and elbow (5.8), and oncology (5.7). Job availability for general orthopaedics was higher than for any subspecialty. The highest percentage of positions advertised were hospital employed jobs compared with private practice and academic positions. CONCLUSIONS: Job availability for fellowship graduates varies notably based on orthopaedic subspecialty. At this time, generalists and subspecialists trained in foot and ankle, adult reconstruction, and trauma seem to be in greatest demand. The reason for the differences in demand is likely multifactorial. Our findings should be considered by orthopaedic residents pursuing fellowship training in addition to weighing both personal interest and financial considerations in their subspecialty choice.

Effect of Ulnar Collateral Ligament Reconstruction on Pitch Accuracy, Velocity, and Movement in Major League Baseball Pitchers.

BACKGROUND: Ulnar collateral ligament (UCL) reconstruction is frequently performed on Major League Baseball (MLB) pitchers. Previous studies have investigated the effects of UCL reconstruction on fastball and curveball velocity, but no study to date has evaluated its effect on fastball accuracy or curveball movement among MLB pitchers. PURPOSE/HYPOTHESIS: The primary purpose of this study was to determine the effects of UCL reconstruction on fastball accuracy, fastball velocity, and curveball movement in MLB pitchers. Our hypothesis was that MLB pitchers who underwent UCL reconstruction would return to their presurgery fastball velocity, fastball accuracy, and curveball movement. The secondary purpose of this study was to determine which factors, if any, were predictive of poor performance after UCL reconstruction. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: MLB pitchers who underwent UCL reconstruction surgery between 2011 and 2012 were identified. Performance data including fastball velocity, fastball accuracy, and curveball movement were evaluated 1 year preoperatively and up to 3 years of play postoperatively. A repeated-measures analysis of variance with a Tukey-Kramer post hoc test was used to determine statistically significant changes in performance over time. Characteristic factors and presurgery performance statistics were compared between poor performers (>20% decrease in fastball accuracy) and non-poor performers. RESULTS: We identified 56 pitchers with a total of 230,995 individual pitches for this study. After exclusion for lack of return to play (n = 14) and revision surgery (n = 3), 39 pitchers were included in the final analysis. The mean presurgery fastball pitch-to-target distance was 32.9 cm. There was a statistically significant decrease in fastball accuracy after reconstruction, which was present up to 3 years postoperatively (P = .007). The mean presurgery fastball velocity of 91.82 mph did not significantly change after surgery (P = .194). The mean presurgery curveball movement of 34.49 cm vertically and 5.89 cm horizontally also did not change significantly (P = .937 and .161, respectively). CONCLUSION: Fastball accuracy among MLB pitchers significantly decreased after UCL reconstruction for up to 3 years postoperatively. There were no statistically significant differences in characteristic factors or presurgery performance statistics between poor and non--poor performers.

Knot of Henry Variation and the Effect on Plantar Flexion Strength.

BACKGROUND: The flexor hallucis longus (FHL) and flexor digitorum longus (FDL) tendons are commonly used for tendon transfer in reconstructive foot and ankle procedures. Some patients experience great toe weakness and loss of push-off strength. The objective of this biomechanical study was to quantify plantarflexion force after FHL and FDL harvest and correlate it to variations in tendon crossover patterns at the knot of Henry to determine if specific patterns have an increased tendency toward forefoot weakness. METHODS: Simulated loads through the Achilles, FHL, and FDL were applied to cadaveric specimens while plantarflexion force was measured using a pressure mapping system. Force was recorded with the FDL and FHL unloaded to simulate tendon transfer. Afterward, specimens were dissected to classify the tendinous slips between the FHL and FDL based on a previously determined system. Functional and anatomical relationships between the classification type and loading patterns were analyzed. RESULTS: There were no statistical differences between the tendon crossover patterns in forefoot force reduction after FHL or FDL harvest. Average decrease in great toe and total forefoot pressure after FHL harvest was 31% and 22%, respectively. Average decrease in lesser toe and total forefoot push-off force after FDL harvest was 23% and 9%, respectively. CONCLUSION: This study quantified loss of plantarflexion force after simulated FHL and FDL harvest and correlated these losses to variations in anatomic crossover patterns at the knot of Henry. Variations at the knot of Henry do not contribute to differences in forefoot weakness. CLINICAL RELEVANCE: The decrease in forefoot pressure seen here would help explain the clinical scenario where a patient does note a loss of great toe strength after FHL transfer.

Radiographic and Magnetic Resonance Imaging of the Symptomatic Synthetic Cartilage Implant.

BACKGROUND: Synthetic Cartilage Implantation (SCI; Cartiva) is a treatment of hallux rigidus associated with mixed clinical outcomes in the United States. Patients with persistent pain typically undergo diagnostic imaging for evaluation. We aimed to characterize the radiologic findings of SCI and surrounding tissues. METHODS: This is a retrospective review of patients treated using SCI who underwent magnetic resonance imaging (MRI) for persistent pain. Metatarsophalangeal (MTP) joint spaces were compared on plain radiographs of the foot immediately postoperatively and at most recent follow-up. MRI of the foot were assessed for dimensions of the implant, bony channel, and presence of peri-implant fluid. Clinical follow-up, including Patient-Reported Outcome Measures Informational System (PROMIS) scores, satisfaction rating, and revision surgery, was collected. Eighteen cases of symptomatic SCI from 16 patients (13 females, 3 males) were included. All but 1 case involved a 10-mm implant. RESULTS: Mean satisfaction rating was 2.25 (1-5 Likert scale). PROMIS scores indicated moderate physical dysfunction (41) and moderate pain interference (63). Six of 16 patients (37.5%) underwent revision surgery at average 20.9 months of follow-up. Plain radiographs over a 13.3-month interval showed joint space narrowing of 2 mm medially and 1.6 mm laterally (P < .001). One hundred percent of cases had radiographic evidence of osteoarthritis (OA) progression. MRI studies were obtained on average 11.5 months postoperatively. The implant diameter averaged 9.7 mm, which mismatched the bony channel diameter of 11.2 mm (P < .001). Fourteen of 18 cases had peri-implant fluid. All cases had edema in the metatarsal, proximal phalanx, and soft tissues. CONCLUSION: Radiographic loss of MTP joint space and progression of arthritis were present for all cases studied. MRI revealed bony channel widening and a smaller implant, with peri-implant fluid suggesting instability at the implant-bone interface. Persistent edema was observed in soft tissues and bone. Diagnostic imaging of SCI in symptomatic patients demonstrated concerning findings that merit further correlation with patient outcomes. LEVEL OF EVIDENCE: Level IV, case series.

Early Outcomes and Complications of Synthetic Cartilage Implant for Treatment of Hallux Rigidus in the United States.

BACKGROUND: The aim of this study was to determine the early outcomes and complications following the implantation of a hydrogel synthetic cartilage implant (SCI, Cartiva) for the treatment of hallux rigidus by a single surgeon. METHODS: A retrospective chart review was performed of consecutive patients who underwent treatment for hallux rigidus with an SCI between August 2016 and April 2018 by a single surgeon. Demographic information, radiographic assessment, and concomitant operative procedures performed were evaluated for all patients. Postoperatively, PROMIS physical function (PF) and pain interference (PI) scores, patient satisfaction, reoperation, conversion to arthrodesis, and need for further clinical treatment were collected. Sixty-four SCIs were implanted in 60 patients. Follow-up averaged 18.5 months (range 12-30 months). RESULTS: 14% (9/64) of patients were very satisfied, 28% (18/64) satisfied, 20% (13/64) neutral, 11% (7/64) unsatisfied, and 27% (17/64) very unsatisfied with their outcome. In addition, 45% of patients underwent additional procedures at the time of SCI, and 23% had a history of surgery on the hallux before implantation. PROMIS PF scores averaged 42 and PROMIS PI scores averaged 60. Overall, 63% completed PROMIS PI, 66% completed PROMIS PF, and 100% completed a satisfaction survey. In addition, 30% (19/64) underwent magnetic resonance imaging (MRI) postoperatively due to pain. There was a 20% reoperation rate, which included an 8% rate of conversion to arthrodesis. CONCLUSION: Synthetic cartilage implantation yielded neutral patient satisfaction, mild pain, and physical dysfunction at early follow-up. We believe patient selection and counseling regarding early postoperative limitations are important before proceeding with SCI. LEVEL OF EVIDENCE: Level IV, case series.

A Review of Perioperative Complications of Outpatient Total Ankle Arthroplasty.

BACKGROUND: Total ankle arthroplasty (TAA) is commonly pursued for patients with painful arthritis. Outpatient TAA are increasingly common and have been shown to decrease costs compared to inpatient surgery. However, there are very few studies examining the safety of outpatient TAA. In this study, we retrospectively reviewed 65 consecutive patients who received outpatient TAA to identify complication rates. METHODS: The medical records of 65 consecutive outpatient TAA from October 2012 to May 2016 with a minimum 6-month follow-up were reviewed. All patients received popliteal and saphenous blocks prior to surgery and were managed with oral pain medication postoperatively. All received a STAR total ankle. Demographics, comorbidities, American Society of Anesthesiologists (ASA) class, and perioperative complications including wound breakdown, infection, revision, and nonrevision surgeries were observed. Mean follow-up was 16.6 ± 9.1 months (range, 6-42 months). RESULTS: There were no readmissions for pain control and 1 patient had a wound infection. The overall complication rate was 15.4%. One ankle (1.5%) had a wound breakdown requiring debridement and flap coverage. This patient thrombosed a popliteal artery stent 1 month postop. The 1 ankle (1.5%) with a wound infection occurred in a patient with diabetes, obesity, hypertension, and rheumatoid arthritis. CONCLUSION: This study demonstrates the safety of outpatient TAA. The combination of regional anesthesia and oral narcotics provided a satisfactory experience with no readmissions for pain control and 1 wound infection. The 1 wound breakdown complication (1.5%) was attributed to arterial occlusion and not outpatient management. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Achilles Tendon Rupture in Elite Athletes.

The management of acute Achilles tendon rupture in elite athletes is a current area of clinical controversy. Recent studies have reported near-equivocal outcomes in patients who undergo either nonsurgical or surgical treatment of Achilles tendon rupture; however, similar functional outcomes may not be observed in elite athletes who are at the highest levels of athletic performance and undergo nonsurgical or surgical treatment of Achilles tendon rupture. Surgeons should understand the risks and benefits of nonsurgical and surgical management of acute Achilles tendon rupture. Surgeons also should understand the accelerated rehabilitation protocols; functional nonsurgical and postoperative rehabilitation protocols; as well as the standard open, percutaneous, and minimally invasive surgical techniques for the management of Achilles tendon rupture from the perspective of a sports medicine foot and ankle specialist.

Lisfranc Injuries in the Elite Athlete.

The management of sports-related Lisfranc injuries is optimized by a detailed understanding of the relevant anatomy, mechanisms of injury, clinical diagnostic maneuvers, imaging, and treatment options for patients with this disabling injury. A lower energy ligamentous variant Lisfranc injury, which was first observed in professional football players, has recently been described. The treatment options for patients with a Lisfranc injury include nonsurgical management, open reduction and internal fixation, suture-button fixation techniques, and arthrodesis.

High-Risk Stress Fractures in Elite Athletes.

Surgeons should understand common factors that predispose high-level athletes to stress injuries as well as the importance of vitamin D and specifics related to vascular supply, location of injury, biomechanics, and susceptibility factors in high-level athletes who have stress injuries. Surgeons should be aware of diagnostic- and management-based recommendations for and the outcomes of anterior tibia, medial malleolus, tarsal navicular, and proximal fifth metatarsal stress fractures in professional athletes.

Management of Osteochondral Lesions of the Talus.

Management strategies for symptomatic osteochondral lesions of the talus are primarily surgical. Treatment options for symptomatic osteochondral lesions of the talus most commonly include bone marrow stimulation techniques, osteochondral autograft transplantation, osteochondral allograft transplantation, autologous chondrocyte implantation, matrix-induced autologous chondrocyte implantation, and particulated juvenile articular cartilage. The selection of the most appropriate treatment option should be based on the specifics of a talar lesion, in particular, lesion size.

Lateral Ankle Instability and Peroneal Tendon Pathology.

Surgeons should understand the anatomic, vascular, biomechanical, and predisposing factors related to lateral ankle instability and peroneal tendon injuries, including peroneal tendinitis and tenosynovitis, peroneal tendon tears and ruptures, as well as peroneal tendon subluxation and dislocation. Surgeons should understand the treatment options and recommendations for patients who have lateral ankle instability and peroneal tendon injuries from the perspective of a sports medicine foot and ankle specialist. In addition, surgeons should be aware of arthroscopic approaches and an algorithm for the treatment of patients who have lateral ankle instability and peroneal tendon injuries.

Realtime Achilles Ultrasound Thompson (RAUT) Test for the Evaluation and Diagnosis of Acute Achilles Tendon Ruptures.

BACKGROUND: Acute complete Achilles tendon ruptures are commonly missed injuries. We propose the Realtime Achilles Ultrasound Thompson (RAUT) test, a Thompson test under ultrasound visualization, to aid in the diagnosis of these injuries. We hypothesized that RAUT testing would provide improved diagnostic characteristics compared with static ultrasound. METHODS: Twenty-two consecutive patients with operatively confirmed acute Achilles tendon ruptures were prospectively evaluated with RAUT testing and static ultrasonography. RAUT video recordings and static ultrasound images from both ruptured and uninjured sides were randomized and graded by a group of novice reviewers and a group of expert attendings. From these observations, sensitivity, specificity, positive predictive value, and negative predictive value for RAUT and static ultrasound were calculated. In addition, κ interobserver coefficients were computed. Forty-seven novice reviewers and 11 foot and ankle attendings made a total of 4136 and 528 observations, respectively. RESULTS: For static ultrasound, sensitivity and specificity were 76.8% and 74.8% for the novice reviewers and 79.6% and 86.4% for the attendings, respectively. For RAUT testing, sensitivity and specificity were 87.2% and 81.1% for the novice group and 86.4% and 91.7% for the attending group, respectively. The κ coefficient was 0.62 and 0.27 for novice and attending RAUT reviewers, indicating substantial and fair agreement, respectively, but only 0.46 and 0.12 for static ultrasonography, representing moderate and slight agreement, respectively. CONCLUSION: RAUT testing was a sensitive and specific test, providing a cost-effective adjunct to the clinical examination when diagnosing acute Achilles tendon ruptures. This test can be used by surgeons with minimal training in ultrasonography. LEVEL OF EVIDENCE: Level II, diagnostic study.

Increased Incidence and Severity of Postoperative Radiographic Hallux Valgus Interphalangeus With Surgical Correction of Hallux Valgus.

BACKGROUND: A previous study has shown an increased radiographic prevalence and severity of hallux valgus interphalangeus (HVIP) after surgical correction of hallux valgus (HV) due to correction of pronation deformity. The purpose of this study was to evaluate the change in pre- and postoperative HVIP deformity with correction of HV with multiple radiographic parameters. METHODS: A retrospective chart review identified all bunion surgeries performed at a single center from July 1, 2009, to September 30, 2012. Exclusion criteria included prior bony surgery to the first ray, inadequate films, nonadult bunion, Akin osteotomy, or surgical treatment other than bunion correction. Pre- and postoperative films were reviewed for 2 HV angular measurements and 5 HVIP measurements, which were compared. The angles measured were hallux valgus angle (HVA), first intermetatarsal angle (IMA), hallux interphalangeus angle (HIA), distal metatarsal articular angle (DMAA), proximal phalangeal articular angle (PPAA), proximal to distal phalangeal articular angle (PDPAA), and total distal deformity (TDD). Prevalence of HVIP was analyzed in pre- and postoperative radiographs. A 1-sided Student t test was used to compare continuous data, and a chi-square test was used to compare categorical data. Ninety-two feet in 82 patients were eligible. RESULTS: The average preoperative HV improved with surgery. Preoperative HVA improved from 27 to 11 degrees (P < .001). Preoperative IMA improved from 13.6 to 6.1 degrees (P < .001). HVIP worsened after surgery. Preoperative HIA increased from 7.2 to 13.2 degrees (P < .001). DMAA worsened from 7.3 to 9.2 degrees (P = .001). PPAA worsened from 3.2 to 6.2 degrees. PDPAA worsened from 6.7 to 8.2 degrees (P < .001). The TDD increased from 14.6 to 17.9 degrees (P < .001). The prevalence of HVIP pre- and postoperatively as defined by HIA increased from 26% to 79% (P < .001) and by PPAA from 12% to 46% (P < .001). CONCLUSION: Initial assessment of preoperative radiographs underestimated HVIP. Postoperative correction of the deformity revealed HVIP that was not obvious preoperatively. LEVEL OF EVIDENCE: Level III, retrospective comparative series.

Effectiveness and Complications Associated With Recombinant Human Bone Morphogenetic Protein-2 Augmentation of Foot and Ankle Fusions and Fracture Nonunions.

BACKGROUND: Recombinant human bone morphogenetic protein-2 (rhBMP-2) has been used to augment bone healing and fusion in a variety of orthopaedic conditions. However, there is a paucity of data evaluating the potential benefits of its use in foot and ankle surgery. The purpose of this study was to investigate the effectiveness and associated complications with the use of rhBMP-2 in high-risk foot and ankle fusions and fracture nonunions. METHODS: A total of 51 cases in 48 patients undergoing foot and ankle fusions or fracture nonunion revisions and considered at high risk for subsequent nonunion were identified through a retrospective review in which rhBMP-2 was used as an augment for bone healing. Rate of union, time to union, and associated complications were evaluated. RESULTS: Forty-seven of 51 high-risk cases treated with rhBMP-2 united for a per-case union rate of 92.2%. Seventy-eight of 82 individual sites treated with rhBMP-2 united for a per-site union rate of 95.1%. Of the successful unions, the mean time to union was 111 days (95% confidence interval, 101-121). There were no statistically significant differences in time to union with regard to supplementation with bone allograft or autograft or size of rhBMP-2 kit used. Complication rates were low. CONCLUSION: rhBMP-2 was a safe and apparently effective adjunct to bony union in high-risk foot and ankle surgeries. Further randomized controlled trials are warranted. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Limited sinus tarsi approach for intra-articular calcaneus fractures.

BACKGROUND: Operative treatment of calcaneal fractures has a historically high rate of wound complications, so the most optimal operative approach has been a topic of investigation. This study reviews the radiographic and clinical outcomes of the use of the sinus tarsi approach for operative fixation of these fractures with attention to the rate of infection and restoration of angular measurements. METHODS: The radiographs and charts of 20 patients with 22 calcaneal fractures were reviewed to assess for restoration of angular and linear dimensions of the calcaneus as well as time to radiographic union. Secondary outcome measures included the rate of postoperative infection, osteomyelitis, revision surgeries, and nonunion. RESULTS: We found a statistically significant restoration of Böhler's angle and calcaneal width. Three of the 22 cases had a superficial wound infection. One patient had revision surgery for symptomatic hardware removal. There were no events of osteomyelitis, deep infection, malunion, or nonunion. CONCLUSION: We found that the sinus tarsi approach yielded similar outcomes to those reported in the literature. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Flexor digitorum brevis transfer for floating toe prevention after Weil osteotomy: a cadaveric study.

BACKGROUND: A floating toe deformity occurs in many patients who undergo Weil osteotomies. It is likely caused by the failure of the windlass mechanism in shortening the metatarsal. For patients who require a proximal interphalangeal (PIP) joint arthroplasty or fusion in addition to a Weil osteotomy, the transfer of the flexor digitorum brevis (FDB) tendon to the PIP joint might restore the windlass mechanism and decrease the incidence of floating toes. METHODS: Fourteen cadaveric foot specimens were examined to determine the effects of changing metatarsal length as well as tensioning the FDB tendon on the angle of the metatarsophalangeal (MTP) joint as a measure of a floating toe. RESULTS: Shortening and lengthening the second metatarsal resulted in a significant change in MTP angle (P = .03 and .02, respectively), though there was no clear relationship found between the amount of change in metatarsal length and the change in MTP angle. Transferring the FDB to a PIP arthroplasty site plantarflexed the MTP joint and corrected floating toes; the change in angle was significant compared with the control and shortening groups (P = .0001 and .002, respectively). CONCLUSION: This study supports the theory that change in length of the metatarsal, possibly via the windlass mechanism, plays a role in the pathophysiology of the floating toe deformity. Tensioning and transferring the FDB tendon into the PIP joint helped prevent the floating toe deformity in this cadaveric model. CLINICAL RELEVANCE: Continued research in this subject will help to refine methods of prevention and correction of the floating toe deformity.

Navicular subluxation as a radiographic finding in Charcot neuroarthropathy.

BACKGROUND: Treatment of patients with Charcot midfoot destruction is a difficult and increasingly common clinical problem. The pathoanatomical features of Charcot neuropathy have been evaluated in only a few studies. This study evaluated whether medial navicular subluxation (adduction of the navicular on the talus) is a radiographic finding present in patients with Charcot neuroarthropathy. METHODS: A retrospective review of 143 consecutive patients diagnosed with Charcot arthropathy of the foot from January 2004 to May 2011 was performed. Patients were identified based on a clinical diagnosis code 713.5 during an outpatient clinic visit with 2 surgeons at a single institution. After exclusion criteria were applied, a series of radiographs of 50 feet in 40 patients were compared with radiographs from an age-matched control group. Radiographic data including talonavicular coverage angle and talonavicular uncoverage percentage were collected. RESULTS: The mean talonavicular coverage angle of the Charcot arthropathy group was 1.5 degrees and of the control group 12.1 degrees (P < .05). The talonavicular uncoverage value for the Charcot arthropathy group was 12.2% and for the control group 22.0% (P < .001). CONCLUSIONS: Medial navicular subluxation was a radiographic finding that was more commonly present in patients with Charcot arthropathy than in a matched control group. It is theorized that this finding is attributable to an unopposed pull of the posterior tibial tendon on the destabilized navicular. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Ipsilateral intact fibula as a predictor of tibial plafond fracture pattern and severity.

BACKGROUND: The objective of this study was to determine whether there is a difference in fracture pattern and severity of comminution between tibial plafond fractures with and without associated fibular fractures using computed tomography (CT). We hypothesized that the presence of an intact fibula was predictive of increased tibial plafond fracture severity. METHODS: This was a case control, radiographic review performed at a single level I university trauma center. Between November 2007 and July 2011, 104 patients with 107 operatively treated tibial pilon fractures and preoperative CT scans were identified: 70 patients with 71 tibial plafond fractures had associated fibular fractures, and 34 patients with 36 tibial plafond fractures had intact fibulas. Four criteria were compared between the 2 groups: AO/OTA classification of distal tibia fractures, Topliss coronal and sagittal fracture pattern classification, plafond region of greatest comminution, and degree of proximal extension of fracture line. RESULTS: The intact fibula group had greater percentages of AO/OTA classification B2 type (5.5 vs 0, P = .046) and B3 type (52.8 vs 28.2, P = .013). Conversely, the percentage of AO/OTA classification C3 type was greater in the fractured fibula group (53.5 vs 30.6, P = .025). Evaluation using the Topliss sagittal and coronal classifications revealed no difference between the 2 groups (P = .226). Central and lateral regions of the plafond were the most common areas of comminution in fractured fibula pilons (32% and 31%, respectively). The lateral region of the plafond was the most common area of comminution in intact fibula pilon fractures (42%). There was no statistically significant difference (P = .71) in degree of proximal extension of fracture line between the 2 groups. CONCLUSIONS: Tibial plafond fractures with intact fibulas were more commonly associated with AO/OTA classification B-type patterns, whereas those with fractured fibulas were more commonly associated with C-type patterns. An intact fibula may be predictive of less comminution of the plafond. The lateral and central regions of the plafond were the most common areas of comminution in tibial plafond fractures, regardless of fibular status. LEVEL OF EVIDENCE: Level III, case control study.