James W. Brodsky, M.D.

Chinitz, N., D. D. Bohl, M. Reddy, S. Tenenbaum, S. Coleman and J. W. Brodsky (2021). “Preoperative Gait Analysis of Peroneal Tendon Tears.” Foot Ankle Int: 10711007211036876.

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BACKGROUND: Little is known regarding the impact of peroneal tendon tears on function. This study quantifies gait changes associated with operatively-confirmed peroneal tendon tears. METHODS: Sixty-five patients with unilateral peroneal tendon tears were prospectively evaluated using preoperative 3D multisegment gait analysis of both limbs. Data were analyzed according to pattern/severity of tears, as confirmed surgically: peroneus brevis tears, reparable (PBR); peroneus brevis tears, irreparable (PBI); peroneus longus tears, irreparable (PLI); and concomitant irreparable tears of both tendons (PBI+PLI). The following parameters were analyzed: ankle sagittal motion, coronal motion, axial rotation, foot progression angle, sagittal power, sagittal moment. RESULTS: Twelve patients (18.5%) had the PBR pattern, 37 (56.9%) PBI, 10 (15.4%) PLI, and 6 (9.2%) PBI+PLI. Compared with the contralateral, nonpathologic extremities, limbs with peroneal tears had diminished ankle sagittal motion (mean 23.14 vs 24.30 degrees, P = .012), ankle/hindfoot axial rotation (6.26 vs 7.23 degrees, P = .001), sagittal moment (1.16 vs 1.29 Nm/kg, P < .001), and sagittal power (1.24 vs 1.47 W/kg, P < .001). The most severe tear patterns had the greatest derangements in multiple parameters of gait (PBI+PLI > PBI or PLI > PBR). For example, all groups except PBR had loss of ankle sagittal moment and/or power in the affected limb, and the greatest losses in moment and power were in the PBI+PLI group (1.22 vs 0.91 Nm/kg, P = .003 for moment; 0.73 vs 1.31 W/kg, P < .001 for power). The PBI+PLI group had a >10-degree varus shift in coronal motion on the affected side (P = .002). CONCLUSION: This is the first study to demonstrate diminished biomechanical function in patients with peroneal tendon tears. In vivo 3-dimensional gait analysis found significant changes in hindfoot motion, ankle motion, and ankle power. Impairments were related to the pattern and severity of the tears, and demonstrated a strong association of peroneal tendon tears with diminished ankle plantarflexion strength. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Taniguchi, A., Alejandro, S.F., Kane, J.M., Daoud, Y., Tanaka, Y., Ford, S.E. and Brodsky, J.W. (2021). “Association of Cavovarus Foot Alignment With Peroneal Tendon Tears.” Foot Ankle Int: 1071100721990348.

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BACKGROUND: Although it is a widely accepted clinical principle that cavovarus deformity predisposes to peroneal tendon problems, there are limited data to support that assumption. This study tested the hypothesis that cavovarus is associated with peroneal tendon tears and evaluated which radiographic measures correlated with that association. METHODS: A retrospective comparison of radiographic measures of cavovarus in 234 consecutive patients operatively treated for chronically symptomatic peroneal tendon tears was compared to a matched control group. Measures included calcaneal pitch, anteroposterior (AP) talometatarsal and talocalcaneal angles, and talonavicular coverage angle. A novel coordinate system analyzed midfoot and hindfoot components of cavovarus. Analysis of variance was used to compare cohorts, and a Tukey-Kramer test used to analyze 3 subgroups of brevis and longus tears, and concomitant tears. RESULTS: The distribution of tears was 73% peroneus brevis, 8% longus, and 19% both tendons. Compared with controls, the study group, and subgroups, had multiple measures of increased cavovarus, including greater calcaneal pitch (P = .0001), decreased AP talo-first metatarsal angle (P = .0001), and increased talonavicular coverage angle (P = .0001). Elevated medial longitudinal arch, and rotational changes in the radiographic profiles of the hindfoot were found with the coordinate system described by Yokokura. CONCLUSION: This study found a statistically significant association of increased cavovarus deformity with peroneal tendon tears, compared to controls. It documented the relative incidence of tears of peroneus brevis, peroneus longus, and concomitant tears in a large surgical series. It demonstrated which simple radiographic angles and complex coordinate measurements of cavovarus deformity were significantly associated with peroneal tendon tears. LEVEL OF EVIDENCE: Level III, retrospective comparative cohort study.

Brodsky, J.W., Scott, D.J., Ford, S., Coleman, S. and Daoud, Y. (2021). “Functional Outcomes of Total Ankle Arthroplasty at a Mean Follow-up of 7.6 Years: A Prospective, 3-Dimensional Gait Analysis.” J Bone Joint Surg Am 103(6): 477-482.

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BACKGROUND: In vivo gait analysis provides objective measurement of patient function and can quantify that function before and after ankle reconstruction. Previous gait studies have shown functional improvement for up to 4 years following total ankle arthroplasty (TAA), but to date, there are no published studies assessing function at ≥5 years following TAA. We hypothesized that patients who underwent TAA would show significant improvements in walking function at a minimum follow-up of 5 years, compared with their preoperative function, as measured by changes in temporospatial, kinematic, and kinetic gait parameters. METHODS: Three-dimensional gait analysis with a 12-camera digital motion-capture system and double force plates was utilized to record temporospatial, kinematic, and kinetic measures in 33 patients who underwent TAA with either the Scandinavian Total Ankle Replacement (Stryker; n = 28) or Salto Talaris Ankle (Integra LifeSciences; n = 5). Gait analysis was performed preoperatively and at a minimum follow-up of 5 years (mean, 7.6 years; range, 5 to 13 years). RESULTS: Significant improvements were observed in multiple gait parameters, with temporospatial increases in cadence (+9.5 steps/min; p < 0.0001), step length (+4.4 cm; p = 0.0013), and walking speed (+0.2 m/s; p < 0.0001), and kinematic increases in total sagittal range of motion (+2.0°; p = 0.0263), plantar flexion at initial contact (+2.7°; p = 0.0044), and maximum plantar flexion (+2.0°; p = 0.0488). Kinetic analysis revealed no loss of peak ankle power, despite patients aging. CONCLUSIONS: To our knowledge, this is the first study to report 7-year functional outcomes of TAA, quantified by objective, in vivo measurements of patient gait. Patients were shown to have sustained improvement in multiple objective parameters of gait compared with preoperative function. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Brodsky, J.W., Jaffe, D., Pao, A., Vier, D., Taniguchi, A., Daoud, Y., Coleman, S. and Scott, D.J. (2021). “Long-term Functional Results of Total Ankle Arthroplasty in Stiff Ankles.” Foot Ankle Int Feb 8;1071100720977847. [Epub ahead of print].

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BACKGROUND: Total ankle arthroplasty (TAA) is advocated over ankle arthrodesis to preserve ankle motion (ROM). Clinical and gait analysis studies have shown significant improvement after TAA. The role and outcomes of TAA in stiff ankles, which have little motion to be preserved, has been the subject of limited investigation. This investigation evaluated the mid- to long-term functional outcomes of TAA in stiff ankles. METHODS: A retrospective study of prospectively collected functional gait data in 33 TAA patients at a mean of 7.6 (5-13) years postoperatively used 1-way analysis of variance and multivariate regression analysis to compare among preoperative and postoperative demographic data (age, gender, body mass index, years postsurgery, and diagnosis) and gait parameters according to quartiles of preoperative sagittal ROM. RESULTS: The stiffest ankles had a mean ROM of 7.8 degrees, compared to 14.3 degrees for the middle 2 quartiles, and 21.0 degrees for the most flexible ankles. Patients in the lowest quartile (Q1) also had statistically significantly lower step length, speed, max plantarflexion, and power preoperatively. Postoperatively, they increased step length, speed, max plantarflexion, and ankle power to levels comparable to patients with more flexible ankles preoperatively (Q2, Q3, and Q4). They had the greatest absolute and relative increases in these parameters of any group, but the final total ROM was still statistically significantly the lowest. CONCLUSION: Preoperative ROM was predictive of overall postoperative gait function at an average of 7.6 (range 5-13) years. Although greater preoperative sagittal ROM predicted greater postoperative ROM, the stiffest ankles showed the greatest percentage increase in ROM. Patients with the stiffest ankles had the greatest absolute and relative improvements in objective function after TAA, as measured by multiple gait parameters. At intermediate- to long-term follow-up, patients with stiff ankles maintained significant functional improvements after TAA. LEVEL OF EVIDENCE: Level III, comparative study.

Brodsky, J.W., Scott, D.J., Ford, S., Coleman, S. and Daoud, Y. (2021). “Functional Outcomes of Total Ankle Arthroplasty at a Mean Follow-up of 7.6 Years: A Prospective, 3-Dimensional Gait Analysis.” J Bone Joint Surg Am Jan 15. [Epub ahead of print].

Full text of this article.

BACKGROUND: In vivo gait analysis provides objective measurement of patient function and can quantify that function before and after ankle reconstruction. Previous gait studies have shown functional improvement for up to 4 years following total ankle arthroplasty (TAA), but to date, there are no published studies assessing function at ≥5 years following TAA. We hypothesized that patients who underwent TAA would show significant improvements in walking function at a minimum follow-up of 5 years, compared with their preoperative function, as measured by changes in temporospatial, kinematic, and kinetic gait parameters. METHODS: Three-dimensional gait analysis with a 12-camera digital motion-capture system and double force plates was utilized to record temporospatial, kinematic, and kinetic measures in 33 patients who underwent TAA with either the Scandinavian Total Ankle Replacement (Stryker; n = 28) or Salto Talaris Ankle (Integra LifeSciences; n = 5). Gait analysis was performed preoperatively and at a minimum follow-up of 5 years (mean, 7.6 years; range, 5 to 13 years). RESULTS: Significant improvements were observed in multiple gait parameters, with temporospatial increases in cadence (+9.5 steps/min; p < 0.0001), step length (+4.4 cm; p = 0.0013), and walking speed (+0.2 m/s; p < 0.0001), and kinematic increases in total sagittal range of motion (+2.0°; p = 0.0263), plantar flexion at initial contact (+2.7°; p = 0.0044), and maximum plantar flexion (+2.0°; p = 0.0488). Kinetic analysis revealed no loss of peak ankle power, despite patients aging. CONCLUSIONS: To our knowledge, this is the first study to report 7-year functional outcomes of TAA, quantified by objective, in vivo measurements of patient gait. Patients were shown to have sustained improvement in multiple objective parameters of gait compared with preoperative function. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.