A finite element model of human hindfoot and its application in supramalleolar osteotomy

BACKGROUND

The majority of the ankle osteoarthritis cases are posttraumatic and affect younger patients with a longer projected life span. Hence, joint-preserving surgery, such as supramalleolar osteotomy becomes popular among young patients, especially those with asymmetric arthritis due to alignment deformities. However, there is a lack of biomechanical studies on postoperative evaluation of stress at ankle joints. We aimed to construct a verifiable finite element model of the human hindfoot, and to explore the effect of different osteotomy parameters on the treatment of varus ankle arthritis.

METHODS

The bones of the hindfoot are reconstructed using normal CT tomography data from healthy volunteers, while the cartilages and ligaments are determined from the literature. The finite element calculation results are compared with the weight-bearing CT (WBCT) data to validate the model. By setting different model parameters, such as the osteotomy height (L) and the osteotomy distraction distance (h), the effects of different surgical parameters on the contact stress of the ankle joint surface are compared.

FINDINGS

The alignment and the deformation of hindfoot bones as determined by the finite element analysis aligns closely with the data obtained from WBCT. The maximum contact stress of the ankle joint surface calculated by this model increases with the increase of the varus angle. The maximum contact stresses as a function of the L and h of the ankle joint surface are determined.

INTERPRETATION

The relationship between surgical parameters and stress at the ankle joint in our study could further help guiding the planning of the supramalleolar osteotomy according to the varus/valgus alignment of the patients.

Changes in clinical outcomes and alignment of the ipsilateral knee and ankle after supramalleolar osteotomy in patients with varus osteoarthritis of the ankle: a short-term follow-up study

PURPOSE

The purpose of this study was to investigate the changes in clinical outcomes and alignment of the ipsilateral knee and ankle in patients with varus ankle osteoarthritis after supramalleolar osteotomy (SMO).

METHODS

We retrospectively reviewed 23 patients (24 ankles) with Takakura II, IIIa and IIIb ankle osteoarthritis treated with SMO between May 2017 and March 2022. The radiologic parameters of ankles contained medial distal tibial angle (TAS), tibiotalar angle (TT), tibial lateral surface (TLS), tibial plafond inclination (TPI) and talar inclination (TI). The radiologic parameters of knees contained medial proximal tibial angle (MPTA), joint line convergence angle (JLCA), the knee joint line orientation relative to ground (G-KJLO) and WBL. Hip-knee-ankle angle (HKA) was also collected. The Takakura system was used for evaluating the ankle osteoarthritis and the Kellgren-Lawrence (KL) system was used for evaluating the knee osteoarthritis. Clinical evaluation of the ankle joints contained American Orthopedic Foot and Ankle Society (AOFAS), range of motion (ROM) and visual analogue scale (VAS). Clinical evaluation of the knee joints contained Japanese Orthopaedic Association Scores (JOA), ROM, VAS.

RESULTS

The mean follow-up times were 20.3 ± 7.3 months (range 12-38). According to the radiologic evaluation, the TAS increased from preoperative 84.7° ± 2.0° to 91.2° ± 1.8° at the last follow-up (P < 0.001). The TPI and TI decreased from 4.4° ± 4.2° and 11.0° ± 5.2° to 0.1° ± 4.7° and 4.1° ± 4.8° (P < 0.001 for both). The TT angel improved from 9.5° ± 4.1° to 4.9° ± 3.3° (P < 0.001). No significant differences were found regarding MPTA, JLCA, G-KJLO, knee WBL and HKA (P > 0.05 for all). The Takakura stage improved after SMO (P < 0.001) whilst the KL stage maintains the similar lever (P > 0.05). According to the clinical evaluation, the AOFAS significantly increased from 67.5 ± 10.6 to 88.5 ± 9.3 and the VAS of the ankle decreased from 4.7 ± 1.6 to 1.2 ± 1.1, whilst there were no changes on VAS and even the JOA and knee ROM after SMO (P > 0.05 for all).

CONCLUSIONS

SMO can alleviate the symptoms of varus ankle osteoarthritis and delay the time for ankle replacement or arthrodesis by redistributing the abnormal stress of the ankle and restoring the congruence of the tibiotalar joint. In addition, it did not induce the clinical symptoms of knee without compromising lower limb alignment or knee joint line orientation in the short term.

LEVEL OF EVIDENCE

Level IV case series.

[Effectiveness comparison of supramalleolar osteotomy and ankle arthrodesis in treatment of inverted ankle osteoarthritis in Takakura 3A stage with talus tilt]

Objective

To compare the effectiveness of supramalleolar osteotomy (SMOT) and ankle arthrodesis (AA) in the treatment of inverted ankle osteoarthritis (OA) in Takakura 3A stage with talus tilt.

Methods

The clinical data of 41 patients with inverted ankle OA in Takakura 3A stage with talus tilt admitted between January 2016 to January 2020 and met the selection criteria were retrospectively analyzed, and they were divided into SMOT group (21 cases) and AA group (20 cases) according to the surgical method. There was no significant difference in baseline data such as gender, age, affected side, cause of injury, and preoperative talar tilt angle (TT), American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, visual analogue scale (VAS) score, short-form 36 health survey scale (SF-36) score, and sagittal range of motion (ROM) between the two groups ( P>0.05). The operation time, intraoperative blood loss, partial weight-bearing time, and complications were recorded in the two groups. AOFAS ankle-hindfoot score, VAS score, SF-36 score, and sagittal ROM were used to evaluate the effectiveness. Bone healing was observed and the time of bony healing was recorded. In the SMOT group, the tibial lateral surface angle (TLS), TT, and the tibial articular surface angle (TAS) were measured on ankle joint weight-bearing anteroposterior and lateral X-ray films and compared with those before operation. And Takakura staging assessment was also performed.

Results

The operation time and intraoperative blood loss in AA group were significantly less than those in SMOT group ( P<0.05). Patients in both groups were followed up 24-36 months, with an average of 28.9 months. Incision infection occurred in 2 patients in SMOT group and 1 patient in AA group, respectively, and no vascular or nerve injury occurred in both groups. The partial weight-bearing time of SMOT group was significantly less than that of AA group ( P<0.05), but there was no significant difference in bony healing time between the two groups ( P>0.05). At last follow-up, the difference of VAS score and SF-36 score before and after operation of AA group were less than those of SMOT group, and the difference of sagittal ROM before and after operation in SMOT group was less than that of AA group, with significant differences ( P<0.05). The difference of AOFAS ankle-hindfoot score before and after operation in AA group was slightly greater than that in SMOT group, but the difference was not significant ( P>0.05). The above scores in both groups significantly improved when compared with those before operation ( P<0.05). Sagittal ROM in AA group was significantly less than that before operation ( P<0.05), while there was no significant difference in SMOT group ( P>0.05). In the SMOT group, 17 patients (81.0%) showed improvement in imaging staging, 2 patients (9.5%) showed no improvement in staging, and 2 patients (9.5%) showed stage aggravation. TLS, TAS, and TT significantly improved when compared with those before operation ( P<0.05). At last follow-up, 2 patients in SMOT group received AA due to pain and stage aggravation, and 1 patient with bone nonunion underwent bone graft. Subtalar joint fusion was performed in 1 case of subtalar arthritis in AA group.

Conclusion

For inverted ankle OA in Takakura 3A stage with talus tilt, both SMOT and AA can significantly releave pain, improve foot function and quality of life, but AA has more definite effectiveness and better patient satisfaction.

Supramalleolar Osteotomies in Cavovarus Foot Deformity: Why Patient-Specific Instruments Make a Difference

Supramalleolar osteotomy enables correction of the ankle varus deformity and is associated with improvement of pain and function in the short term and long term. Despite these beneficial results, the amount of surgical correction is challenging to titrate and the procedure remains technically demanding. Most supramalleolar osteotomies are currently planned preoperatively on 2-dimensional weight-bearing radiographs and executed peroperatively using free-hand techniques. This article encompasses 3-dimensional planning and printing techniques based on weight-bearing computed tomography images and patient-specific instruments to correct ankle varus deformities.

Efficacy of supramalleolar osteotomy in the treatment of traumatic ankle joint varus deformity in adolescents

BACKGROUND

Supramalleolar osteotomy (SMOT) has emerged as a valuable treatment for ankle varus deformity; however, there are fewer reports of treatment outcomes in adolescents. The purpose of this study was to investigate the radiologic and clinical outcomes of SMOT for the treatment of traumatic ankle joint varus deformity (TAVD) in adolescents.

METHODS

We reviewed 32 adolescent cases who underwent SMOT between February 2017 and February 2022 for TAVD. Radiologic assessment included tibial anterior surface angle (TAS), talar tilt angle (TT), and tibial lateral surface angle (TLS) preoperatively and at 3 months and 12 months postoperatively, and clinical assessment was performed using American Orthopaedic Foot and Ankle Society (AOFAS) scores, Visual Analogue Scale (VAS) scores, and ankle dorsiflexion-plantarflexion ROM including preoperative and 6 months postoperative and 12 months postoperative.

RESULTS

All 32 patients were followed up completely with a mean follow-up of (20.3 ± 3.2) months. From the radiologic outcomes, the mean preoperative TAS improved from 61.53 ± 3.74 to 88 ± 1.72 at 12 months postoperatively, the mean preoperative TT decreased from 2.25 ± 1.32 to 0.5 ± 0.57 at 12 months postoperatively, the mean preoperative TLS improved from 76.72 ± 0.21 to 79.34 ± 1.52 at 12 months postoperatively, the differences between the above preoperative and 12 months postoperative radiologic outcomes were statistically significant (p < 0.05), the mean preoperative AOFAS score improved from 65.5 ± 9.40 to 92.34 ± 4.00 at 12 months postoperatively, the mean preoperative VAS score decreased from 2.44 ± 1.24 to 0.78 ± 0.75 at 12 months postoperatively, and the mean preoperative range of motion (ROM) of ankle improved from 50.16 ± 7.46 to 55.78 ± 4.77 at 12 months postoperatively. The differences between the above preoperative and 12 months postoperative clinical results were statistically significant (p < 0.05).

CONCLUSION

Our study demonstrated that SMOT was effective in correcting TAVD and significantly improving ankle function in adolescents, and that it is an efficient and successful method for restoring ankle joint congruence and normal hindfoot alignment.

Changes in the subtalar joint alignment after supramalleolar osteotomy for varus ankle arthritis

BACKGROUND

The subtalar joint may compensate for tibio-talar deformity, but what would happen to the joint after the deformity was corrected is not well known. Supramalleolar osteotomy (SMOT) is an effective procedure for the treatment of varus deformity of ankle arthritis. The objective of this study was to investigate the subtalar joint alignment pre and postoperatively following SMOT, and the factors which influenced the alignment of the subtalar joint.

METHODS

Thirty-one patients with varus ankle arthritis (Takakura stage 2, 3a and 3b) who were treated using SMOT were retrospectively reviewed. The subtalar and ankle joint alignment was measured on weightbearing radiograph and weightbearing computerized tomography (WBCT).

RESULTS

The foot and ankle offset (FAO), tibial articular surface angle (TAS), tibio-talar surface angle (TTS), and subtalar vertical angle (SVA) were significantly corrected (P＜0.05). The subtalar inclination angle (SIA) decreased in 19 patients and increased in the other 12 cases after the SMOT (P＜0.001). The shift of subtalar joint (ΔSIA) showed an inverse correlation with the preoperative FAO (P＜0.001, r = -0.621).

CONCLUSIONS

The shift of subtalar joint after SMOT could maintain the neutral position of the hindfoot and showed a negative correlation with the preoperative FAO. The ΔSIA was greater in the severer preoperative hindfoot deformity.

LEVEL OF EVIDENCE

Level IV, case series.

Evaluation of clinico-radiological outcome of fibular valgization osteotomy with supra-malleolar osteotomy in patients with ankle osteoarthritis

PURPOSE

There are controversies about combining distal tibia medial opening-wedge osteotomy (DTMO) with fibular valgization osteotomy (FVO) when performing supramalleolar osteotomy (SMO) for medial ankle osteoarthritis. This study aimed to assess the effect of FVO on the coronal translation of the mechanical axis by comparing the improvement of radiological indices after DTMO with and without FVO.

METHODS

Forty-three ankles (mean follow-up: 42.0 months) were reviewed after SMO. Among them, 35/43 (81.4%) underwent DTMO with FVO, while 8/43 (18.6%) underwent DTMO only. To evaluate the effect of FVO radiologically, the medial gutter space (MGS) and talus centre migration (TCM) were measured.

RESULTS

Post-operatively, MGS and TCM were not significantly different after DTMO only and DTMO with FVO. However, the improvement of MGS was significantly higher in the combined FVO group (0.8 mm (standard deviation [SD] 0.8 mm) vs. 1.5 mm (SD 0.8 mm); p = 0.015). More lateral translation of the talus was achieved in the FVO group (5.1 mm (SD 2.3 mm) vs. 7.5 mm (SD 3.0 mm); p = 0.033). However, the changes in the MGS and TCM were not significantly correlated with the clinical outcomes (p > 0.05).

CONCLUSION

Our radiological evaluation confirmed a significant medial gutter space widening and lateral talar translation after the addition of FVO. The SMO with fibular osteotomy allows greater shifting of the talus and, therefore, the weight-bearing axis.

Correction of ankle varus deformity using patient-specific dome-shaped osteotomy guides designed on weight-bearing CT: a pilot study

BACKGROUND

Dome-shaped supramalleolar osteotomies are a well-established treatment option for correcting ankle deformity. However, the procedure remains technically demanding and is limited by a two-dimensional (2D) radiographic planning of a three-dimensional (3D) deformity. Therefore, we implemented a weight-bearing CT (WBCT) to plan a 3D deformity correction using patient-specific guides.

METHODS

A 3D-guided dome-shaped supramalleolar osteotomy was performed to correct ankle varus deformity in a case series of five patients with a mean age of 53.8 years (range 47-58). WBCT images were obtained to generate 3D models, which enabled a deformity correction using patient-specific guides. These technical steps are outlined and associated with a retrospective analysis of the clinical outcome using the EFAS score, Foot and Ankle Outcome Score (FAOS) and visual analog pain scale (VAS). Radiographic assessment was performed using the tibial anterior surface angle (TAS), tibiotalar angle (TTS), talar tilt angle (TTA), hindfoot angle (HA), tibial lateral surface angle (TLS) and tibial rotation angle (TRA).

RESULTS

The mean follow-up was 40.8 months (range 8-65) and all patients showed improvements in the EFAS score, FAOS and VAS (p < 0.05). A 3-month postoperative WBCT confirmed healing of the osteotomy site and radiographic improvement of the TAS, TTS and HA (p < 0.05), but the TTA and TRA did not change significantly (p > 0.05).

CONCLUSION

Dome-shaped supramalleolar osteotomies using 3D-printed guides designed on WBCT are a valuable option in correcting ankle varus deformity and have the potential to mitigate the technical drawbacks of free-hand osteotomies.

LEVEL OF EVIDENCE

Level 5 case series.

Supramalleolar osteotomy for the treatment of ankle osteoarthritis leads to favourable outcomes and low complication rates at mid-term follow-up: a systematic review

PURPOSE

The purpose of this systematic review was to evaluate both the clinical and radiographic outcomes following supramalleolar osteotomy (SMO) in patients with ankle osteoarthritis, and to analyse the level of evidence (LOE) and quality of evidence (QOE) of the included studies.

METHODS

A systematic review of the MEDLINE, EMBASE, and Cochrane Library databases was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies reporting clinical data following SMO for the treatment of ankle osteoarthritis were included and assessed. The level and quality of evidence of the included studies were also evaluated.

RESULTS

Twenty-four studies with 1160 patients (1182 ankles) were included. Overall, 78.8% patients presented with post-traumatic ankle osteoarthritis. The weighted mean AOFAS score improved from 52.6 ± 9.7 (range 33.8-78.4) preoperatively to 78.1 ± 5.7 postoperatively at weighted mean follow-up of 50.4 ± 18.6 months (range 24.5-99.0).  The most frequently utilised radiographic parameter was the tibial anterior surface angle, which improved from a preoperative weighted mean of 86.3° ± 5.6° (range 76.0°-102.0°) to a postoperative weighted mean of 89.9° ± 3.7° (range 84.9°-99.6°). The complication rate was 5.1% with non-union as the most commonly reported complication (1.6%). Secondary procedures were carried out in 28.2% of patients, the most common of which was implant and hardware removal (17.6%). The failure rate was 6.8%. Two studies were LOE II, 3 studies were LOE III, and 19 studies were LOE IV. The mean Modified Coleman Methodology Score was 59.3 ± 6.6 and the mean MINORS criteria score of all the included studies was 9.5 ± 3.7.

CONCLUSION

This systematic review demonstrates good clinical and radiological outcomes, together with a low failure rate at mid-term follow-up following supramalleolar osteotomy in patients with ankle osteoarthritis. However, a moderate reoperation rate (28.2%) was reported. A low failure rate (6.8%) was reported, which must be interpreted in light of the shortcomings of the design of the included studies and a relatively short follow-up period. In addition, there is a low level and quality of evidence in the current literature with inconsistent reporting of data which underscores the need for further higher quality research to be conducted. Our review highlights that SMO may be an effective and safe procedure in the setting of early-to-intermediate-stage ankle osteoarthritis.

LEVEL OF EVIDENCE

IV.

Outcomes of oblique supramalleolar osteotomy without fibular osteotomy for congruent- and incongruent-type medial ankle arthritis

BACKGROUND

Although high talar tilt and ankle mortise incongruence are risk factors for supramalleolar osteotomy (SMO), no study on lateral talofibular joint congruence exists. We aimed to evaluate the outcomes of oblique SMO without fibular osteotomy for medial ankle arthritis and compare them according to the lateral talofibular joint congruity.

METHODS

Forty-eight ankles were retrospectively reviewed and divided according to preoperative talofibular joint congruity (congruent, 22 [45.8%] vs. incongruent, 26 [54.2%]).

RESULTS

The mean VAS score, AOFAS score, and modified Takakura stage were significantly improved. No significant differences were noted in clinical outcomes, but the mean postoperative tibiotalar angle and difference between the upper and lower talofibular gaps were significantly different in both groups (p = 0.004 and p = 0.009, respectively). The mean Takakura stage at 1 and 2 years after surgery was higher in the incongruent group (p = 0.013, p = 0.012).

CONCLUSION

This procedure was effective against early- to mid-stage medial ankle arthritis. Radiographic arthritic grade changed according to the talofibular joint congruity.

Comparisons between ankle distraction arthroplasty and supramalleolar osteotomy for treatment of post-traumatic varus ankle osteoarthritis

BACKGROUND

Ankle distraction arthroplasty and supramalleolar osteotomy were both options for post-traumatic varus ankle arthritis (VAA), but their comparative effectiveness was scarcely reported. This study aimed to compare the outcomes of two operative methods for treatment of Takakura-Tanaka stage 3 post-traumatic VAA.

METHODS

This was a retrospective study, comprising 73 consecutive patients who presented with Takakura-Tanaka stage 3 post-traumatic VAA treated by either ankle distraction arthroplasty (n = 32) or supramalleolar osteotomy (n = 41) from January 2016 to December 2019. All patients had a minimum 24-month follow-up assessments. The outcome measures were visual analog scale (VAS), the American Orthopedic Foot & Ankle Society (AOFAS) ankle-hindfoot scores, complications, patient-rated overall satisfaction and ankle function.

RESULTS

At an average of 32 months (range, 24-52 months) follow-up, significant improvement was observed for VAS, AOFAS, range of motion (ROM) and most radiographic parameters (except for TAS and TLS for ankle distraction arthroplasty group) compared to preoperative baselines (p < 0.05) for both groups. However, both groups did not differ significantly in terms of VAS or AOFAS, excellent and good rate (78.1% versus 85.4%, p = 0.422), overall rate of postoperative complications (28.1% vs. 17.1%, p = 0.257), or various radiographic parameters (e.g. tibial anterior surface angle, talar tilt angle and tibial lateral surface angle) (all p > 0.05). The ankle distraction arthroplasty group had a better postoperative ankle motion than did the supramalleolar osteotomy group, in terms of plantarflexion (37.8 ± 4.2 vs. 30.4 ± 3.6, p = 0.006), dorsiflexion (36.5 ± 6.4 vs. 28.3 ± 5.5, p = 0.004), varus (32.1 ± 4.5 vs. 27.1 ± 3.1, p = 0.017) and valgus (28.4 ± 3.7 vs. 25.2 ± 2.8, p = 0.046).

CONCLUSIONS

Both operative treatments are effective for Takakura-Tanaka stage 3 post-traumatic VAA. In practice, individualized treatment option tailored to the ankle condition and patients' specific need should be considered.

LEVEL OF EVIDENCE

 III, retrospective comparative series.

Correction of Sagittal Plane Deformity of the Distal Tibia

Distal tibia sagittal plane deformities are a frequent finding in tibial malunions (antecurvatum or recurvatum) or ankle posttraumatic arthritis (anterior or posterior ankle arthritis). They should be evaluated in all deformities using long leg and tibia radiographs. Measuring the anterior distal tibia angle is necessary to evaluate the deformity severity. To evaluate the magnitude of secondary talar anterior or posterior displacement, the tibial axis to talus ratio and/or the talar lateral process position relative to the tibia axis should be measured. Anterior closing or opening wedge osteotomies are the recommended treatment options for posterior ankle arthritis or anterior ankle arthritis, respectively.

Ankle distraction arthroplasty (ADA): A brief review and technical pearls

Ankle distraction arthroplasty (ADA) is a procedure based on the concept that mechanical unloading of an arthritic joint will initiate a healing response in the subchondral bone and articular cartilage. ADA utilizes the patient's own healing response, preserves joint motion, and is a great option for patients with osteoarthritis who are not ready for prosthetic arthroplasty or fusion. The procedure is well described and technically simple and adjunctive biologic therapies are exciting for joint regeneration. Complications are minor, and more serious adverse events are avoidable. Supramalleolar osteotomy pairs well with ankle distraction but requires some analysis and planning.

Fibular osteotomy is helpful for talar reduction in the treatment of varus ankle osteoarthritis with supramalleolar osteotomy

BACKGROUND

There have been debates on the necessity of fibular osteotomy (FO) in supramalleolar osteotomy (SMOT) for the treatment of varus ankle osteoarthritis. The purpose of the current study was to compare the clinical and radiological outcomes between SMOT with and without FO in the treatment of varus ankle osteoarthritis.

METHODS

The SMOT group included 39 patients, and the SMOT with FO group included 24 patients. The basic information reached no significant difference between groups. The American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, Ankle Osteoarthritis Scale (AOS), modified Takakura stage and range of motion (ROM) were used for the functional evaluation. The radiologic parameters were assessed at the last follow-up to compare the degree of talar reduction between the two groups.

RESULTS

Both groups achieved significant improvements in AOFAS scores, modified Takakura stage, as well as AOS pain and functional scores (P < 0.001). The ROM of the ankle joint in the SMOT group was significantly decreased (P = 0.022). In both groups, all of the radiological parameters were significantly improved (P < 0.01). The tibiofibular clear space (TFCS) was significantly widened in the SMOT group (P < 0.001). No significant difference was found between the two groups according to the functional outcomes. However, the talar tilt angle (TT) and hindfoot alignment angle (HFA) in the SMOT with FO group were significantly smaller than those in the SMOT group (P < 0.05). The TFCS was significantly widened in the SMOT group (P = 0.001). The medial displacement of the talus (MDT) was better reduced in the SMOT with FO group (P = 0.006).

CONCLUSION

SMOT is a promising procedure for functional improvement and malalignment correction in varus ankle osteoarthritis but reduces ankle range of motion. If SMOT is combined with FO, talar tilt and medial displacement will be better reduced.

Distal tibial oblique osteotomy for reconstruction of ankle joint congruity and stability

Teramoto distal tibial oblique osteotomy (DTOO) is a joint-preserving surgery for ankle osteoarthritis (AOA). However, there are few articles on the radiological assessment of DTOO. The purpose of this study was to report the clinical outcomes and radiological evaluations of weight-bearing radiographs before and after DTOO. We retrospectively reviewed 52 patients who underwent DTOO between 2007 and 2018. We recorded the Tanaka-Takakura classification, fixation methods, Japanese Society for Surgery of the Foot Ankle/Hindfoot Scale (JSSF scale), and complications. The tibial articular surface angle (TAS), medial malleolar angle (MMA), tibial lateral surface angle (TLS), talar tilt angle (TTA), and tibiotalar surface angle (TTS) were evaluated using weight-bearing ankle radiographs. The median patient age was 66 years, and the mean follow-up duration was 46 ± 23 months. Two stage 2, 9 stage 3a, 30 stage 3b, and 11 stage 4 according to the Tanaka-Takakura classification were performed using DTOO. The JSSF scale improved significantly from 39.9 ± 13.8 before surgery to 87.2 ± 7.5 after surgery. Seven cases were fixed using a locking plate, and 45 cases were fixed using a circular external fixator. The TAS, MMA, TLS, TTA, and TTS significantly changed before and after DTOO. Radiological evaluation indicated that DTOO influences talar behavior during weight-bearing, and improves the clinical outcomes of AOA.

Simulated operation combined with patient-specific instrumentation technology is superior to conventional technology for supramalleolar osteotomy: a retrospective comparative study

OBJECTIVE

Over the past seven years, our team has designed a simulated operation combined with patient-specific instrumentation (SO-PSI) assisted supramalleolar osteotomy (SMOT) method and applied it in the clinic. This study aimed to evaluate the differences between SO-PSI technology and conventional operation (CO) technology for SMOT in preoperative planning, intraoperative application, and postoperative curative effect.

METHODS

We retrospectively analyzed SMOT data collected from our hospital between October 2014 and December 2018. Patients (n = 28) were enrolled and divided into CO (n = 17) and SO-PSI (n = 11) groups; mean follow-up time was 33.4 (range, 13 to 59) months. We statistically analyzed and compared perioperative data, accuracy of preoperative planning, intraoperative application, difference between pre- and post-operative radiologic ankle angles, changes in American Orthopaedic Foot & Ankle Society (AOFAS) score, visual analogue scale (VAS) score, range of ankle motion, and Takakura stage after surgery.

RESULTS

All ankle alignments and positions were recovered for both groups. Compared with the CO group, the SO-PSI group had a shorter mean operating time and postoperative hospital stay, a decreased number of fluoroscopy examinations, lower albumin reduction, longer preoperative planning time and preoperative hospital stay, and increased hospitalization expenses. In the SO-PSI group, comparison of ankle angles at preoperative planning and postoperatively revealed good correlation, while this was not the case in the CO group. Mean tibial ankle center discrepancy for the SO-PSI group was 1.86 ± 1.06 mm. On follow-up, all radiologic parameters for the two groups improved significantly; however, the improvement of the tibial anterior surface angle and tibiotalar tilt angle for the SO-PSI group were more obvious than those for the CO group. AOFAS score, VAS score, ankle range of motion, and Takakura stage improved after surgery in both groups; however, the improvements in the SO-PSI group were greater than those in the CO group overall.

CONCLUSIONS

SO-PSI technology can facilitate accurate and rapid preoperative planning for SMOT. In general, compared with conventional technology, SO-PSI has advantages for preoperative planning, intraoperative application, and postoperative curative effect.

Perioperative axial loading computed tomography findings in varus ankle osteoarthritis: Effect of supramalleolar osteotomy on abnormal internal rotation of the talus

BACKGROUND

We used axial loading computed tomography (AL CT) to evaluate preoperative and postoperative talocrural joints of patients who underwent supramalleolar osteotomy (SMO) to treat varus ankle osteoarthritis.

METHODS

We performed retrospective analyses of 16 patients (18 feet) who underwent SMO including fibular osteotomy. Radiographic assessment was performed with weightbearing radiographs and AL CT. Clinical outcomes were assessed based on American Orthopedic Foot & Ankle Society (AOFAS) scale, visual analog scale (VAS) for pain, and Foot and Ankle Ability Measure (FAAM).

RESULTS

The mean 2-year follow-up tibial-ankle surface angle, talar tilt angle, Takakura stage, and tibial-lateral surface angle were all significantly different relative to preoperative parameters (P<.05). The mean 6-month follow-up talus rotation ratio was significantly corrected compared to the preoperative value (P=.001). The mean 2-year follow-up AOFAS, VAS at gait, and FAAM scores were all significantly improved relative to preoperative measurements (P=.001).

CONCLUSIONS

Abnormal internal rotation of the talus in mild to moderate varus ankle osteoarthritis found on AL CT was significantly corrected after SMO.

LEVEL OF EVIDENCE

Therapeutic Level IV.

Supramalleolar Distal Tibiofibular Osteotomy for Medial Ankle Osteoarthritis: Current Concepts

The supramalleolar osteotomy is a joint-preserving surgical procedure. It is a very good treatment option for the asymmetric varus ankle and medial compartment osteoarthritis. The primary objective of the procedure is to shift medial concentration of stress toward the lateral intact articular cartilage to redistribute the joint loads during ambulation. Several studies have shown that deformities of the ankle result in uneven load distribution in the ankle joint, which eventually leads to articular cartilage degeneration. Since the lateral articular cartilage is intact, joint-sacrificing procedures such as total ankle replacement or ankle arthrodesis are not the most appropriate treatment choices for medial compartment arthritis. Results of supramalleolar osteotomies are very promising in terms of functional outcome and pain relief. In younger patients with medial compartment varus ankle osteoarthritis or even with a normal tibial anterior surface angle, supramalleolar osteotomies can be performed to realign the ankle to promote regeneration of the asymmetrically damaged cartilage. In this review article, we will discuss the indications, complications, surgical techniques, and outcomes of the supramalleolar osteotomy reported in the current literature.

Supramalleolar osteotomy in post-traumatic valgus ankle osteoarthritis

PURPOSE

To assess how the level of the deformity, the stage of the osteoarthritic process, and the role of additional surgeries impact radiographic and clinical outcomes following an extra-articular medial closing supramalleolar osteotomy for treatment of post-traumatic valgus ankle osteoarthritis.

METHODS

About 56 consecutive patients who underwent an extra-articular medial closing wedge osteotomy for post-traumatic valgus ankle osteoarthritis were retrospectively analyzed. Subgroups were formed according to the pre-operative level of deformity and preoperative stage of ankle osteoarthritis. Additional surgical steps required to achieve a properly balanced hindfoot were also noted. Radiographic and clinical outcomes of each subgroup were compared with each other, and the role of additional surgical steps required to achieve a balanced hindfoot was investigated.

RESULTS

Radiographic and clinical outcomes improved significantly between pre-operative assessment and the last follow-up. Patients with a pre-operative supramalleolar deformity showed superior radiographic outcomes compared to patients with an intra-articular deformity. Clinical outcomes did not differ significantly between these two subgroups. The pre-operative stage of ankle osteoarthritis significantly impacted radiographic outcomes but did not influence clinical outcome measures. An additional fibula or calcaneus osteotomy was necessary for 55% and 23% of all patients, respectively.

CONCLUSION

Extra-articular medial closing supramalleolar osteotomies show satisfactory mid- to long-term radiographic and clinical outcomes in patients with post-traumatic valgus ankle osteoarthritis.

Supramalleolar osteotomy combined with lateral ligament reconstruction and talofibular immobilization for varus ankle osteoarthritis with excessive talar tilt angle

Background

Although supramalleolar osteotomy is the main joint-preserving method for the treatment of varus ankle osteoarthritis, it tends to be ineffective when ankle osteoarthritis presents in combination with an excessive talar tilt angle. The purpose of this study was to present a new surgical technique, supramalleolar osteotomy combined with lateral ligament reconstruction and talofibular immobilization, for the treatment of varus ankle osteoarthritis with an excessive talus tilt angle and to evaluate the clinical and radiological results.

Methods

From January 2013 to October 2016, a total of 17 patients with 17 cases of varus ankle arthritis with excessive talar tilt angles (larger than 7.3°) underwent surgical treatment using our new technique. The American Orthopaedic Foot and Ankle Society (AOFAS) clinical ankle-hindfoot scale and a visual analogue scale (VAS) were used to evaluate ankle function and pain before surgery and at the last follow-up. The medial distal tibial angle (MDTA), anterior distal tibial angle (ADTA), talar tilt angle (TTA), and hindfoot moment arm values (HMAVs) were evaluated on weight-bearing radiographs acquired preoperatively and at the last follow-up.

Results

The AOFAS score improved significantly from 45.8 ± 2.1 before surgery to 84.8 ± 1.8 after surgery (p < 0.001), and the VAS score decreased from 4.9 ± 0.4 to 1.1 ± 0.2 (p < 0.001). The MDTA, TTA, and HMAV changed from 80.9° ± 0.4° to 90.1° ± 0.4°, 11.7° ± 0.6° to 1.4° ± 0.3°, and 12.6 mm ± 0.8 mm to 4.2 mm ± 0.6 mm, respectively (each p < 0.001). The ADTA showed no obvious change (p = 0.370). The staging of 11 cases (65%) improved. Intramuscular vein thrombosis of the lower limbs occurred in 1 patient 1 week after surgery, and superficial infection occurred in 1 patient.

Conclusions

Supramalleolar osteotomy combined with lateral ligament reconstruction and talofibular immobilization can correct the load of the weight-bearing ankle and effectively improve the ankle function. As the talar tilt angle can be significantly improved after surgery, this technique can be used for the treatment of varus ankle osteoarthritis with an excessive TTA.

Stability of supramalleolar osteotomies using different implants in a sawbone model

BACKGROUND

With ankle arthritis often affecting young patients, joint-sparing treatments instead of total joint replacement should be considered. Only a few implants were specially developed for supramalleolar osteotomies (SMOT). This study was performed to analyse the stability of different implants and their appropriateness for SMOT.

METHODS

Twenty-five bone models (Sawbone Europe, Malmö, Sweden) were used for biomechanical testing. SMOT were performed as a uniplanar osteotomy, leaving 5 mm of lateral bone intact with a standardized gap of 8 mm. Five different plates commonly used for SMOT were assessed. For axial stability, the constructs were tested during 100 cycles for each load (150N and 800N) at a rate of 0.5 Hz. For rotational stability, each construct was subject to 100 cycles of 5 Nm torque at a rate of 0.25 Hz, performing three runs with an axial preload of 0N, 150N, or 800N. Ultimate axial load was performed for one-half and ultimate rotational load was performed for the other half of the constructs. In addition, the stiffness of the different constructs after failure was tested.

RESULTS

All constructs showed high stability and could be tested until maximum cyclic load. There was no significant difference between the five plates, neither for stiffness (axial or rotational) nor for failure load (axial or rotational). One plate indicated superiority in axial failure testing without any significant difference.

CONCLUSION

All implants could be tested until maximum load. The intact hinge apparently provides enough support to compensate for lower moment of inertia of some plates.

LEVEL OF EVIDENCE

Not applicable.

Current Advancements in Ankle Arthrodiastasis

Ankle arthrodiastasis offers an option for patients with end-stage primary or posttraumatic ankle osteoarthritis. The process allows for a joint salvage procedure as an alternative to arthrodesis or ankle implant arthroplasty. The distraction within the joint optimizes the intraarticular environment to permit equilibration of hydrostatic pressure, promoting subchondral morphoangiogenesis, and decreases subchondral sclerosis, thereby mitigating pain. This article highlights new advances and useful adjunctive procedures in this interesting approach to the management of ankle pain secondary to loss of functional joint surface.

Supramalleolar Osteotomies

Distal tibial malalignment can result from posttraumatic malunion, physeal disturbances, congenital or metabolic diseases, and degenerative arthritis. Malalignment leads to an altered load distribution across the joint leading to early ankle joint arthritis. If a substantial part of the joint is salvageable, ankle fusion or joint replacement is not always the best option. Realignment of the distal tibia with a joint-sparing supramalleolar osteotomy is a valuable procedure in correcting deformity at the distal tibia. The goal of a supramalleolar osteotomy is to restore axial alignment. Several studies have demonstrated the successes of the osteotomy in improving function and relieving pain.

Changes in ankle joint motion after Supramalleolar osteotomy: a cadaveric model

Background

Malalignment of the ankle joint has been found after trauma, by neurological disorders, genetic predisposition and other unidentified factors, and results in asymmetrical joint loading. For a medial open wedge supramalleolar osteotomy(SMO), there are some debates as to whether concurrent fibular osteotomy should be performed. We assessed the changes in motion of ankle joint and plantar pressure after supramalleolar osteotomy without fibular osteotomy.

Methods

Ten lower leg specimens below the knee were prepared from fresh-frozen human cadavers. They were harvested from five males (10 ankles)whose average age was 70 years. We assessed the motion of ankle joint as well as plantar pressure for SS(supra-syndesmotic) SMO and IS(intra-syndesmotic) SMO. After the osteotomy, each specimen was subjected to axial compression from 20 N preload to 350 N representing half-body weight. For the measurement of the motion of ankle joint, the changes in gap and point, angles in ankle joint were measured. The plantar pressure were also recorded using TekScan sensors.

Results

The changes in the various gap, point, and angles movements on SS-SMO and IS-SMO showed no statistically significant differences between the two groups. Regarding the shift of plantar center of force (COF) were noted in the anterolateral direction, but not statistically significant.

Conclusions

SS-SMO and IS-SMO with intact fibula showed similar biomechanical effect on the ankle joint. We propose that IS-SMO should be considered carefully for the treatment of osteoarthrosis when fibular osteotomy is not performed because lateral cortex fracture was less likely using the intrasyndesmosis plane because of soft tissue support.

Osteochondral autograft transplantation with biplanar distal tibial osteotomy for patients with concomitant large osteochondral lesion of the talus and varus ankle malalignment

Background

Osteochondral lesions of the talus (OLTs) are amongst the most common foot and ankle disorders. Varus ankle malalignment causes stress concentration on medial side of the joint, resulting in OLTs and osteoarthritis. For large symptomatic OLTs (>10 mm), Osteochondral autograft transplantation is usually recommended. This article highlights biplanar distal tibial osteotomy as an approach and management for patients with concomitant large OLTs and varus ankle malalignment.

Methods

From January 2012 to July 2014, 13 patients (6 male and 7 female) underwent surgery in our faculty and their average age was 55.4 (ranging from 34 to 69) years old. Oblique medial malleolar osteotomy was performed to expose the talar lesion, followed by an osteochondral autograft transplantation and distal tibial opening-wedge osteotomy. Weight-bearing X-rays were conducted and used for the measurement of radiographic parameters such as the tibial articular surface (TAS) and tibial lateral surface (TLS) angles. Ankle function of the subjects was evaluated according to the American Orthopaedic Foot and Ankle Society-Ankle and Hindfoot score (AOFAS-AH) questionnaires and Visual Analog Scale (VAS).

Results

11 patients completed the follow-up over a mean period of 21.2 months. The average area of talar lesion was 135.9 mm² while the average depth was 11.4 mm. The mean time for osseous union was 8.5 weeks. Donor site morbidity was not recorded in any of the cases. The mean AOFAS-AH and VAS improved from 53 to 90 points (p < 0.05) and 6.7 to 1.9 points (p < 0.05) respectively. The mean TAS angle improved from 83.1 to 90.3° (p < 0.05).

Conclusions

Biplanar distal tibial osteotomy with the combination of osteochondral autograft transplantation could be used to address patients with concomitant large OLTs and varus ankle malalignment as this technique provides excellent visualization of the talar defect, favorable biomechanical environment for the ankle joint with high rate of good and excellent results.

The role of fibular for supramalleolar osteotomy in treatment of varus ankle arthritis: a biomechanical and clinical study

Background

Supramalleolar osteotomy (SMOT) is a well-accepted treatment method for mid-stage varus ankle osteoarthritis (OA). However, few studies have examined the role of fibular osteotomy in SMOT. The objective of the current study was to compare the biomechanical and clinical outcomes of SMOT with and without fibular osteotomy.

Methods

Eight cadaveric lower legs with 10° varus/valgus SMOT models were tested using a Tekscan ankle sensor. Tibiotalar joint contact with and without fibular osteotomy conditions were compared. Forty-one varus ankle OA patients treated with SMOT were included; 22 underwent fibular osteotomy, and 19 did not. The Maryland foot score and radiological angles were used for clinical evaluation.

Results

The mean contact area and pressure did not differ significantly between normal and varus/valgus conditions with the fibula preserved. After fibular osteotomy, the mean contact area decreased and the mean contact pressure increased significantly in varus and valgus conditions (P < 0.01). The loading center moved to the opposite direction with and without fibular osteotomy in varus/valgus conditions. After a mean follow-up of 36.6 months (range 17–61), there was no significant difference in the Maryland scores of the two groups. However, in the fibular osteotomy group, the talar tilt angle decreased (P < 0.05), and the tibiocrural angle improved significantly (P < 0.01).

Conclusions

Fibular osteotomy facilitates the translation of tibiotalar contact pressure and is helpful for varus ankle realignment in patients with large talar tilts and small tibiocrural angles.

[Effect of distal tibial varus and valgus deformity on joint contact]

OBJECTIVE

?To study the effect of different degrees of distal tibial varus and valgus deformities on the tibiotalar joint contact, and to understand the role of fibular osteotomy.

METHODS

?Eight cadaveric lower legs were used for biomechanical study. Nine conditions were included: normal ankle joint (group A), 10° varus (group B), 5° varus (group C), 5° valgus (group D), 10° valgus (group E) with fibular preserved, and 10° varus (group F), 5° varus (group G), 5° valgus (group H), and 10° valgus (group I) after fibular osteotomy. The joint contact area, contact pressure, and peak pressure were tested; and the translation of contact force center was observed.

RESULTS

?The joint contact area, contact pressure, and peak pressure had no significant difference between group A and groups B to E (P>0.05). After fibular osteotomy, the contact area decreased significantly in groups F and I when compared with group A (P<0.05); the contact pressure increased significantly in groups F, H, and I when compared with group A (P<0.05); the peak pressure increased significantly in groups F and I when compared with group A (P<0.05). There were two main anterior-lateral and anterior-medial contact centers in normal tibiotalar joint, respectively; and the force center was in anterior-lateral part, just near the center of tibiotalar joint. While the fibula was preserved, the force center transferred laterally with increased varus angles; and the force center transferred medially with increased valgus angles. However, the force center transferred oppositely to the medial part with increased varus angles, and laterally with increased valgus angles after fibular osteotomy.

CONCLUSIONS

?Fibular osteotomy facilitates the tibiotalar contact pressure translation, and is helpful for ankle joint realignment in suitable cases.

Arthroscopic evaluation of persistent pain following supramalleolar osteotomy for varus ankle osteoarthritis

PURPOSE

The purposes of this study were to investigate pain experienced by patients after supramalleolar osteotomy for varus ankle osteoarthritis and to analyse correlations between this pain and arthroscopic findings.

METHODS

Twenty-nine patients (31 ankles) who underwent arthroscopic evaluation after supramalleolar osteotomy were reviewed retrospectively. The visual analog scale (VAS) was used to assess pain, and the patients were instructed to record the time point, location, and character of the pain. The tibial-ankle surface angle, talar tilt, and tibial-lateral surface angle were measured on radiographs.

RESULTS

The location, time point, and character of the pain experienced by the patients changed after supramalleolar osteotomy. The mean VAS score was significantly improved after supramalleolar osteotomy at the time of the arthroscopic evaluation (P < 0.001) and improved further after the arthroscopic procedures (P = 0.026). During arthroscopy, pathologic lesions such as adhesions, synovitis, and soft-tissue impingement were identified. A significant correlation was found between adhesions and dull pain and pain at rest (P = 0.016 and P = 0.005, respectively). In addition, soft-tissue impingement in the lateral gutter was significantly correlated with dull pain, pain at rest, and clicking pain (P = 0.001, P = 0.035, and P = 0.042, respectively). No significant correlations were found between post-operative radiographic measurements and development of pathologic lesions.

CONCLUSIONS

With the use of arthroscopy, persistent pain experienced after supramalleolar osteotomy was found to be associated with adhesions, synovitis, and soft-tissue impingement in medial and lateral gutters of the ankle. Arthroscopy can be helpful in identifying and treating painful lesions commonly seen after supramalleolar osteotomy. An understanding of these painful lesions will help patients have more realistic expectations regarding the supramalleolar osteotomy.

LEVEL OF EVIDENCE

Case series study, Level IV.

Additional mesenchymal stem cell injection improves the outcomes of marrow stimulation combined with supramalleolar osteotomy in varus ankle osteoarthritis: short-term clinical results with second-look arthroscopic evaluation

Background

Supramalleolar osteotomy (SMO) is reported to be an effective treatment for varus ankle osteoarthritis by redistributing the load line within the ankle joint. Mesenchymal stem cells (MSCs) have been proposed as a new treatment option for osteoarthritis on the basis of their cartilage regeneration ability. The purpose of this study was to compare the clinical, radiological, and second-look arthroscopic outcomes between MSC injection with marrow stimulation and marrow stimulation alone in patients with varus ankle osteoarthritis who have undergone SMO.

Methods

In this retrospective study, 62 patients (64 ankles) with varus ankle osteoarthritis underwent second-look arthroscopy at a mean of 12.8 months after arthroscopic marrow stimulation combined with SMO; 33 ankles were subjected to marrow stimulation alone (group I), and 31 were subjected to marrow stimulation with MSC injection (group II). Clinical outcome measures included a visual analog scale (VAS) for pain and the American Orthopaedic Foot and Ankle Society (AOFAS) score. Radiological outcome variables included the tibial–ankle surface (TAS), talar tilt (TT), and tibial–lateral surface (TLS) angles. In second-look arthroscopy, cartilage regeneration was evaluated using the International Cartilage Repair Society (ICRS) grade.

Results

The mean VAS score improved significantly from 7.2 ± 1.0 to 4.7 ± 1.4 in group I and from 7.3 ± 0.8 to 3.7 ± 1.5 in group II at the final follow-up (P < 0.001 for both groups). The mean AOFAS score also improved significantly from 61.7 ± 5.8 to 80.9 ± 6.7 in group I and from 60.6 ± 6.1 to 85.2 ± 5.1 in group II at the final follow-up (P < 0.001 for both groups). There were significant differences in the mean VAS and AOFAS scores between groups at the final follow-up (P = 0.002 and 0.010, respectively). At second-look arthroscopy, there were significant differences in ICRS grades between groups(P = 0.015 for medial aspect of the talar dome, P = 0.044 for medial aspect of the tibial plafond, and P = 0.005 for articular surface of the medial malleolus). ICRS grades were significantly correlated with clinical outcomes in both groups (all P < 0.05). Mean TAS, TT, and TLS angles improved significantly after SMO in both groups but were not significantly correlated with clinical outcomes or ICRS grade (all n.s.).

Conclusions

The clinical and second-look arthroscopic outcomes of MSC injection with marrow stimulation were better compared to those of marrow stimulation alone in patients with varus ankle osteoarthritis who have undergone SMO. Furthermore, the ICRS grade is significantly correlated with clinical outcome.

Extraarticular Supramalleolar Osteotomy for Managing Varus Ankle Osteoarthritis, Alternatives for Osteotomy: How and Why?

The supramalleolar osteotomy has been reported to be a joint preserving surgery with good clinical outcome for asymmetric ankle osteoarthritis, especially varus ankle osteoarthritis. Conventional supramalleolar osteotomy of the tibia and fibula creates angulation and translation of the ankle joint without changing the width of the ankle mortise. Distal tibial oblique osteotomy improved the preoperative clinical and radiological parameters; however, mean talar tilt angle did not decrease. Assessment of the ankle arthritis in sagittal, axial, and coronal planes may be helpful to achieve a decrease of the talar tilt in ankle osteoarthritis.

Supramalleolar Osteotomies for Posttraumatic Malalignment of the Distal Tibia

Supramalleolar osteotomies of the tibia (SMOT) for posttraumatic distal tibial malalignment has shown to reduce pain, improve function and radiographic signs of osteoarthritis, and delay ankle arthrodesis or total joint replacement. The procedure also protects the articular cartilage from further degenerative processes by shifting and redistributing loads in the ankle joint. It is technically demanding and requires extensive preoperative planning. The type of osteotomy (opening vs closing wedge) does not influence the final outcome. However, based on the limited evidence, a grade I treatment recommendation has been given for supramalleolar osteotomies of the tibia to treat mild to moderate ankle arthritis in the presence of distal tibial malalignment.

Supramalleolar Osteotomy: Indications and Surgical Techniques

Supramalleolar osteotomies are a surgical treatment option for asymmetric varus or valgus ankle arthritis where at least 50% of the joint surface is spared. Procedure selection requires significant preoperative planning for appropriate execution. Thus, the surgeon must be familiar with the principles of deformity correction. With appropriate patient selection and proper preoperative planning, the procedure has been shown to yield excellent results, redistributing forces more evenly across the ankle joint by restoring the mechanical axis of the lower leg with minimal complications.

Supramalleolar osteotomy and ankle arthrodiastasis for juvenile posttraumatic ankle arthritis

Numerous techniques have been described for posttraumatic ankle arthritis with or without an associated lower extremity deformity in the adult population. These surgical procedures may include, but are not limited to, ankle exostectomy with joint resurfacing, ankle arthrodiastasis, ankle arthroplasty, and ankle arthrodesis. Associated deformities may also be addressed with supramalleolar osteotomies, tibia or fibular lengthening, and calcaneal osteotomies. In juvenile patients, surgical treatment options for posttraumatic ankle arthritis can be challenging, especially when an associated deformity is present. This article describes a combined supramalleolar osteotomy and ankle arthrodiastasis for a juvenile patient with posttraumatic ankle arthritis and valgus deformity.

Supramalleolar osteotomy: techniques, indications and outcomes in a series of 83 cases

INTRODUCTION

Supramalleolar osteotomy is an alternative surgical procedure for the management of asymmetric early arthritis of the ankle. The main goal of this retrospective study was to evaluate the clinical and radiological benefits of supramalleolar osteotomy. The secondary goal was to identify prognostic factors to help decide upon this therapeutic indication.

MATERIALS AND METHODS

Eighty-three patients, mean age 45 years old (17-79), presenting with post-traumatic asymmetric early arthritis of the ankle were followed up for a mean 3.5 years (1-14 years). Sixty-two patients presented with a varus deformity (mean: 13°), and 21 with a valgus deformity (mean: 17.5°). The presence of a preoperative clinical 'sidewalk sign' was looked for and it was considered positive if pain improved when the patient walked on a surface slope that was tilted in the opposite direction of their deformity. A functional preoperative evaluation and at the final follow-up were performed using the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hind foot scale. The frontal deformity was measured by the Meary angle on a weight-bearing X-ray. Varus deformities were treated by a lateral closing wedge supramalleolar osteotomy or a medial opening wedge supramalleolar osteotomy. Valgus deformities were treated by a lateral opening wedge or a medial closing wedge supramalleolar osteotomy.

RESULTS

At last follow-up, the mechanical axis in the varus group was 1.3° and 7.5° in the valgus group. The AOFAS score significantly improved (P<0.001) by 15 points in patients with a varus deformity and 13 points in patients with a valgus deformity. A positive sidewalk sign (disappearance of pain) was correlated with a good outcome and had a positive predictive value of 0.88 (CI: 0.77-0.95) (P<0.001).

DISCUSSION

The supramalleolar osteotomy is a conservative therapeutic surgical option for the management of arthritis of the ankle associated with varus or valgus deformities. The results are satisfactory for indications of arthritis with varus and valgus deformities and a positive 'sidewalk' sign (pain relief on a slope surface tilted in the opposite direction of the deformity).

LEVEL OF EVIDENCE

Level IV: retrospective case series.

Joint-preserving surgery of valgus ankle osteoarthritis

Patients with posttraumatic ankle osteoarthritis (OA) typically present with asymmetric involvement of the tibiotalar joint, resulting in valgus or varus deformity of the ankle and hindfoot. Without appropriate treatment, patients with asymmetric ankle OA typically develop full end-stage ankle OA. Ankles with valgus deformities suffer from a lateral joint overload with subsequent lateral tibiotalar joint degeneration, which causes further lateral load shift. In these cases patients may benefit from joint-preserving realignment surgery to unload the degenerated lateral area and normalize joint biomechanics. This article describes the authors' algorithm for the treatment of patients with asymmetric valgus ankle OA.

Joint-preserving surgery of asymmetric ankle osteoarthritis with peritalar instability

A varus or valgus talar tilt that increases under weight-bearing is commonly seen in osteoarthritic ankles. Loss of peritalar stability may be the underlying cause for the talus shifting and rotating on the calcaneonavicular surfaces, as given by applied forces. The instability pattern and the resulting deformity can be assessed and classified using weight-bearing conventional radiographs. Appropriate osseous balancing may be the most appropriate treatment to restore a regular position of talus within the ankle mortise. In cases with severe peritalar instability, subtalar fusion may be advised. Soft tissue reconstruction may be needed to achieve physiologic balance of the hindfoot complex.