Short-term Results of Magnetic Resonance Imaging after Ankle Distraction Arthroplasty.

BACKGROUND: Ankle distraction arthroplasty has emerged as an alternative treatment for ankle arthritis. There are few reports on the magnetic resonance imaging (MRI) findings after distraction arthroplasty. This study sought to determine whether there are positive changes on MRI after ankle distraction and improvements on X-ray. Additionally, patient-reported outcomes and joint range of motion (ROM) after ankle distraction are described. MATERIALS AND METHODS: Thirty-two patients (mean age 49 years) who underwent ankle distraction had pre-operative and one-year postoperative MRIs, which were graded using a modified whole-organ magnetic resonance imaging score (WORMS). Ankle joint space and ROM were measured. A non-validated three-item questionnaire was administered to assess functional outcomes. RESULTS: Although the anterior quadrant of the ankle showed a trend to improvement in cartilage morphology on the postoperative MRI, the WORMS did not demonstrate a significant difference in any of its subcategories. While reduction in joint osteophytes was observed and maintained short term, this was mainly due to resection intraoperatively. X-rays revealed a significant increase in joint space, and there was a significant increase in ankle dorsiflexion. Eight-seven percent of the patients were satisfied with their functional outcome. CONCLUSION: At short-term follow-up, MRI scores after ankle distraction arthroplasty did not demonstrate significant improvement despite positive changes on X-ray and improved clinical outcomes and ankle ROM. Further study on larger patient numbers with longer follow-up is required. LEVEL OF EVIDENCE: IV, Case Series. HOW TO CITE THIS ARTICLE: Haleem AM, Galal S, Nwawka OK, et al. Short-term Results of Magnetic Resonance Imaging after Ankle Distraction Arthroplasty. Strategies Trauma Limb Reconstr 2020;15(3):157-162.

Does the Surgical Correction of Tibial Torsion with Genu Varum Produce Outcomes Similar to Those in Varus Correction Alone?

The aim of this article is to study the relationship between tibia vara and external tibial torsion in adults. The following questions were asked: (1) what is the incidence of rotational deformity in patients with genu varum and (2) do patients who undergo correction of tibial torsion with genu varum have similar outcomes to those who undergo simple tibia vara correction? In this study, 69 patients (138 limbs) underwent bilateral proximal tibial osteotomy for the correction of genu varum. Patients with simple coronal plane deformity (varus alone) were treated with either a monolateral external fixator or a hexapod frame. Those with concomitant external tibial torsion were treated with circular external fixation. The primary outcome was the ability to achieve the desired correction of alignment in the coronal, sagittal, and axial planes. Secondary outcomes included a postoperative Knee Injury and Osteoarthritis Outcome Score (KOOS) and a routine patient satisfaction questionnaire. The incidence of tibial torsion among the entire group of patients with bilateral tibia vara was 46% and overwhelmingly external in direction. The two groups had some significant differences in demographics with torsion patients tending to be younger and thinner. The final mechanical axis deviation and medial proximal tibial angle values for both groups did not differ significantly (p = 0.956). The postcorrection thigh-foot axis was not significantly different between the two groups (p = 0.666). Time to union was not significant (p > 0.999). KOOS was not different between the two groups in symptoms, pain, activities of daily living, and return to sport. There was a difference in the quality of life score between the two groups (p = 0.044). There was no difference between the two groups regarding the patient questionnaire. Based on the finding of this analysis, the incidence of rotational malalignment with genu varum is close to 50%. The recognition of this close association with external tibial torsion deformity may allow for further insights into the role of rotation in varus deformity-related knee pathology and treatment. Patients can expect nearly identical outcomes from this surgery.

What is the Utility Of a Limb Lengthening and Reconstruction Service in an Academic Department of Orthopaedic Surgery?

BACKGROUND: Limb lengthening and reconstruction surgery is a relatively new subspecialty of orthopaedic surgery in the United States. Despite increased awareness and practice of the specialty, it is rarely vested as a separate clinical service in an academic department of orthopaedic surgery. We have had experience growing such a dedicated service within an academic department of orthopaedic surgery over the past 9 years. QUESTIONS/PURPOSES: We explored (1) the use of a limb deformity service (LDS) in an academic department of orthopaedic surgery by examining data on referral patterns, our clinical volume, and academic productivity; and (2) the surgical breadth of cases comprising the patients of the LDS in an academic department of orthopaedic surgery by examining data on caseload by anatomic sites, category, and surgical techniques/tools. METHODS: We (SRR, ATF, EWB) retrospectively examined data on numbers of surgical cases and outpatient visits from the limb lengthening and complex reconstruction service at the Hospital for Special Surgery from 2005 to 2013 to evaluate growth. We studied 672 consecutive surgical cases performed by our service for a sample period of 1 year, assessing referral patterns within and outside our medical center, anatomic region, surgical category, and surgical technique/tool. Academic productivity was measured by review of our service's publications. RESULTS: During the time period studied (2005-2013), outpatient and surgical volume significantly increased by 120% (1530 to 3372) and 105% (346 to 708), respectively, on our LDS. Surgical volume growth was similar to the overall growth of the department of orthopaedic surgery. Referrals were primarily from orthopaedic surgeons (56%) and self/Internet research (25%). Physician referrals were predominantly from our own medical center (83%). Referrals from within our institution came from a variety of clinical services. Forty-nine peer-reviewed articles and 23 book chapters were published by staff members of our service. Anatomic surgical sites, surgical categories, and technique/tools used on our LDS were diverse, yet procedures were specialized to the discipline of limb deformity. CONCLUSIONS: There is a substantial role for an LDS within an academic department of orthopaedic surgery. With establishment of a dedicated service comes focus and resources that establish an environment for growth in volume, intramural and extramural referral, and purposeful research and education. The majority of referrals were from orthopaedic surgeons from our own medical center, suggesting needfulness. The LDS provides patients access to specialized surgery. The number of intramural referrals suggests that the specialty service helps retain patients within our academic orthopaedic department. Future research will try to determine if such a dedicated service leads to improved outcomes, efficiency, and value. LEVEL OF EVIDENCE: Level IV, retrospective study.

What risk factors predict usage of gastrocsoleus recession during tibial lengthening?

BACKGROUND: Tibial lengthening is frequently associated with gastrocsoleus contracture and some patients are treated surgically. However, the risk factors associated with gastrocsoleus contracture severe enough to warrant surgery during tibial lengthening and the consistency with which gastrocsoleus recession (GSR) results in a plantigrade foot in this setting have not been well defined. QUESTIONS/PURPOSES: We compared patients treated with or without GSR during tibial lengthening with respect to (1) clinical risk factors triggering GSR use, (2) ROM gains and patient-reported outcomes, and (3) complications after GSR. METHODS: Between 2002 and 2011, 95 patients underwent tibial lengthenings excluding those associated with bone loss; 82 (83%) were available for a minimum followup of 1 year. According to our clinical algorithm, we performed GSR when patients had equinus contractures of greater than 10° while lengthening or greater than 0° before or after lengthening. Forty-one patients underwent GSR and 41 did not. Univariate analysis was performed to assess independent associations between surgical characteristics and likelihood of undergoing GSR. A multivariate regression model and receiver operating characteristic curves were generated to adjust for confounders and to establish risk factors and any threshold for undergoing GSR. Chart review determined ROM, patient-reported outcomes, and complications. RESULTS: Amount and percentage of lengthening, age, and etiology were risk factors for GSR. Patients with lengthening of greater than 42 mm (odds ratio [OR]: 4.13; 95% CI: 1.82, 9.40; p = 0.001), lengthening of greater than 13% of lengthening (OR: 3.88; 95% CI: 1.66, 9.11; p = 0.001), and congenital etiology (OR: 1.90; 95% CI: 0.86, 4.15; p = 0.109) were more likely to undergo GSR. Adjusting for all other variables, increased amount lengthened (adjusted OR: 1.05; 95% CI: 1.02, 1.07; p < 0.001) and age (adjusted OR: 1.02; 95% CI: 0.99, 1.05; p = 0.131) were associated with undergoing GSR. Patients gained 24° of ankle dorsiflexion after GSR. Self-reported functional outcomes were similar between patients with or without GSR. Complications included stretch injury to the posterior tibial nerve leading to temporary and partial loss of plantar sensation in two patients. CONCLUSIONS: Dorsiflexion was maintained and/or restored similarly among patients with or without GSR when treated under our algorithm. Functional compromise was not seen after GSR. Identification of patients at risk will help surgeons indicate patients for surgery. Acute dorsiflexion should be avoided to minimize risk of injury to the posterior tibial nerve. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Recombinant human BMP-2 increases the incidence and rate of healing in complex ankle arthrodesis.

BACKGROUND: Although its FDA-approved applications are limited, the pro-osteogenic benefits of recombinant human BMP-2 (rhBMP-2) administration have been shown in off-label surgical applications. However, the effects of rhBMP-2 on ankle fusions are insufficiently addressed in the literature, which fails to include a case-control study of adequate sample size to evaluate the efficacy of rhBMP-2 treatment. QUESTIONS/PURPOSES: In this study we asked whether rhBMP-2 treatment (1) would increase the rate of successful ankle fusion in complex patients (patients with comorbidities associated with poor surgical healing) compared with a control group of patients undergoing ankle fusion who did not receive rhBMP-2; (2) would reduce total time wearing a frame when compared with the control group; (3) would result in a difference in the percentage of bone bridging between the group treated with rhBMP-2 and the control group, as determined by CT scans 3 months after surgery; and (4) would encounter an equal rate of complications different from untreated patients. METHODS: A retrospective chart study was performed on 82 patients who, because of a host of comorbidities associated with poor healing, required a complex ankle arthrodesis with the Ilizarov technique. The first 40 patients did not receive rhBMP-2, whereas the subsequent 42 patients received intraoperative rhBMP-2. Time wearing the frame was determined by chart review; decision to remove the frame was made by the surgeon based on quantitative bone bridging measured using a CT scan taken 3 months after fusion. RESULTS: Patients treated with rhBMP-2 were more likely to obtain fusion after the initial surgery (93% versus 53%, p < 0.001; OR, 11.76; 95% CI, 3.12-44.41), spent less total time wearing the frame (124 versus 161 days, p < 0.01), and showed more bone bridging on CT scans (48% versus 32%, p < 0.05). All patients with greater than 30% bone bridging observed on CT scans 3 months postoperatively achieved successful union without further intervention. CONCLUSIONS: Our findings suggest that rhBMP-2 is a beneficial adjunct for selected groups of patients undergoing complex ankle arthrodesis. CT is a promising modality in the assessment of bone healing in ankle fusion. A proper randomized controlled trial remains necessary to fully describe the efficacy of rhBMP-2 in accelerating bone healing.

Complex ankle arthrodesis using the Ilizarov method yields high rate of fusion.

BACKGROUND: Ankle arthrodesis may be achieved using the Ilizarov method. Comorbidities, such as diabetes, Charcot neuroarthropathy, osteomyelitis, leg length discrepancy, and smoking, can make an ankle fusion complex and may be associated with lower rates of healing. QUESTIONS/PURPOSES: We asked if (1) smoking and other comorbidities led to lower fusion rates, (2) time wearing the frame affected outcome, and (3) simultaneous tibial lengthening improved fusion rates. METHODS: We retrospectively studied 101 patients who underwent complex ankle fusion using the Ilizarov technique. The median time wearing the frame was 25 weeks (range, 10-65 weeks). Twenty-four patients had simultaneous tibial lengthening. The minimum followup for 91 of the 101 patients was 27 months (median, 65 months; range, 27-134 months). RESULTS: Fusion was achieved in 76 of 91 patients. Smoking was associated with a 54% rate of nonunion. Fifteen of 19 patients with Charcot neuroarthropathy achieved union but had a high rate of subsequent subtalar joint failure. Time wearing the frame did not affect union rates. Tibial lengthening did not improve ankle fusion rates. CONCLUSION: Smokers should be warned of the high risk of nonunion and we recommend they quit smoking. We also recommend surgeons recognize the higher nonunion rate in patients with Charcot neuroarthropathy. We believe tibial lengthening should not be performed to enhance healing at the fusion site. LEVEL OF EVIDENCE: Level IV, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.