Supramalleolar osteotomy in post-traumatic valgus ankle osteoarthritis

Radiographic Analysis of Valgus Ankle Deformity With or Without Medial Longitudinal Arch Collapse

BACKGROUND

Establishing a surgical plan for ankle deformities necessitates a comprehensive understanding of the deforming forces involved, and the morphology of the ankle deformity plays an important role as well. Valgus tibiotalar tilt development has mostly been described in patients with a low medial longitudinal arch, as seen in progressive collapsing foot deformity (PCFD). However, some valgus ankles demonstrate no radiographic evidence of a collapsed medial arch. This study aims to investigate whether there are differences in the radiographic morphology of valgus ankle deformities between patients with and without a low medial longitudinal arch to explore if they have different etiologies.

METHODS

We retrospectively reviewed patients who underwent surgical treatment for asymmetric valgus ankle deformity at our institution between 2017 and 2021. Patients with a valgus tibiotalar tilt (TT) greater than 4 degrees and Meary angle greater than 30 degrees (mean: 38.9) were included in the PCFD group (n = 29). The non-PCFD group (n = 24) with TT greater than 4 degrees and Meary angle less than 4 degrees (mean: 0.3) was also established. In the weightbearing ankle anteroposterior view, the TT and medial distal tibial angle were measured. Additionally, to assess the mediolateral position of the talus, the talar center migration (TCM) and lateral talar dome-plafond distance (LTD-P) ratio in the coronal plane were measured. In weightbearing computed tomography (WBCT), the degree of axial plane talocalcaneal subluxation and the prevalence of sinus tarsi bony impingement were assessed. Intergroup comparison was conducted.

RESULTS

Both groups demonstrated a similar degree of TT, with a mean of 11.6 degrees in the PCFD group and 13.7 degrees in the non-PCFD group (P = .2330). However, the PCFD group showed a significantly greater TCM and LTD-P ratio compared with those of the non-PCFD group (P < .0001), indicating that PCFD patients have a more medially translated talus in ankle anteroposterior radiographs. WBCT showed that the PCFD group on average had 18 degrees greater axial plane talocalcaneal subluxation (P < .0001) and 52% higher prevalence of sinus tarsi bony impingement (P = .0002) compared with the non-PCFD group.

CONCLUSION

This study suggests that valgus ankles may exhibit different radiographic morphologies depending on the status of the longitudinal arch. Valgus ankles in PCFD patients tend to have a more medially translated talus. This finding may suggest the presence of different deforming forces between the 2 groups and may indicate the need for different treatment strategies to address talar tilt.

LEVEL OF EVIDENCE

Level III, case-control.

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.

The Unloading Effect of Supramalleolar Versus Sliding Calcaneal Osteotomy for Treatment of Osteochondral Lesions of the Medial Talus: A Biomechanical Study

Background

In patients with osteochondral lesion, defects of the medial talus, or failed cartilage surgery, a periarticular osteotomy can unload the medial compartment.

Purpose

To compare the effects of supramalleolar osteotomy (SMOT) versus sliding calcaneal osteotomy (SCO) for pressure redistribution and unloading of the medial ankle joint in normal, varus-aligned, and valgus-aligned distal tibiae.

Study Design

Controlled laboratory study.

Methods

Included were 8 cadaveric lower legs with verified neutral ankle alignment (lateral distal tibial angle [LDTA] = 0°) and hindfoot valgus within normal range (0°-10°). SMOT was performed to modify LDTA between 5° valgus, neutral, and 5° varus. In addition, a 10-mm lateral SCO was performed and tested in each position in random order. Axial loading (700 N) of the tibia was applied with the foot in neutral alignment in a customized testing frame. Pressure distribution in the ankle joint and subtalar joint, center of force, and contact area were recorded using high-resolution Tekscan pressure sensors.

Results

At neutral tibial alignment, SCO unloaded the medial joint by a mean of 10% ± 10% or 66 ± 51 N (P = .04) compared with 6% ± 12% or 55 ± 72 N with SMOT to 5° valgus (P = .12). The achieved deload was not significantly different (ns) between techniques. In ankles with 5° varus alignment at baseline, SMOT to correct LDTA to neutral insufficiently addressed pressure redistribution and increased medial load by 6% ± 9% or 34 ± 33 N (ns). LDTA correction to 5° valgus (10° SMOT) unloaded the medial joint by 0.4% ± 14% or 20 ± 75 N (ns) compared with 9% ± 11% or 36 ± 45 N with SCO (ns). SCO was significantly superior to 5° SMOT (P = .017) but not 10° SMOT. The subtalar joint was affected by both SCO and SMOT, where SCO unloaded but SMOT loaded the medial side.

Conclusion

SCO reliably unloaded the medial compartment of the ankle joint for a neutral tibial axis. Changes in the LDTA by SMOT did not positively affect load distribution, especially in varus alignment. The subtalar joint was affected by SCO and SMOT in opposite ways, which should be considered in the treatment algorithm.

Clinical Relevance

SCO may be considered a reliable option for beneficial load-shifting in ankles with neutral alignment or 5° varus malalignment.

The Role of Supramalleolar Osteotomies in Ankle Arthritis

The supramalleolar osteotomy (SMO) is a joint-preserving surgical procedure that allows realignment of the ankle joint in severe deformity secondary to arthritis. This osteotomy realigns the mechanical axis to provide better weight distribution through the ankle joint. With an aligned mechanical axis, the overloaded asymmetric ankle joint will shift toward the preserved joint area in a valgus or varus ankle joint. The SMO also can be used via a staged approach to correct severe deformity in an end-stage arthritic ankle before total ankle arthroplasty to optimize the implant's longevity and improve overall functional outcomes.

Lower limb alignment in patients with primary valgus ankle arthritis: A comparative analysis with patients with varus ankle arthritis and healthy controls

BACKGROUND

While it is commonly acknowledged that the combined effect of lower limb orientation and ankle and hindfoot alignment play a fundamental role in ankle arthritis, supramalleolar/lower limb alignment has received less attention in valgus ankle arthritis. The purpose of this study was to analyze the lower limb alignment of patients with valgus ankle arthritis with primary origin, compared to that of varus ankle arthritis and normal controls. We hypothesized that patients with valgus ankle arthritis would have the opposite pattern of lower limb alignment as those with varus ankle arthritis.

METHODS

A retrospective radiographic analysis was performed on 61 patients (62 ankles, mean age, 59.3 ± 12 years) with primary valgus ankle arthritis. On preoperative radiographs, seven parameters, including talar tilt angle, medial distal tibial angle (MDTA), talar center migration, anterior distal tibial angle, talo-first metatarsal (Meary's) angle, hindfoot moment arm (HMA), and mechanical axis deviation (MAD), were measured and compared to those of primary varus ankle arthritis (n = 55; mean age, 59.7 ± 8.1 years) and control patients (n = 59; mean age, 29.3 ± 7.3 years).

RESULTS

The valgus group had a significantly lower mean MDTA than the control group (p < 0.0001), indicating a varus distal tibial plafond in comparison to the control group. Meary's angle and HMA were significantly lower in the valgus group compared to the varus group (p < 0.05 and p < 0.0001, respectively), indicating a lower medial longitudinal arch and valgus hindfoot alignment. On whole limb radiographs, the valgus group showed a greater MAD than the control group, indicating varus lower limb alignment (p < 0.05). However, the MAD did not differ significantly between the valgus and varus groups (p = 0.7031).

CONCLUSION

Our findings indicate that a significant proportion of ankles with primary valgus arthritis have a varus tibial plafond and a varus lower limb mechanical axis. This study contributes to our understanding of primary valgus ankle arthritis and suggests that lower limb alignment should be analyzed and considered throughout valgus ankle arthritis realignment procedures.

Reconstructive Surgery and Joint-Sparing Surgery in Valgus and Varus Ankle Deformities: A Comprehensive Review

Osteoarthritis (OA) of the ankle affects about 1% of the world’s adult population, causing an important impact on patient lives and health systems. Most patients with ankle OA can show an asymmetrical wear pattern with a predominant degeneration of the medial or the lateral portion of the joint. To avoid more invasive ankle joint sacrificing procedures, joint realignment surgery has been developed to restore the anatomy of the joints with asymmetric early OA and to improve the joint biomechanics and symptoms of the patients. This narrative, comprehensive, all-embracing review of the literature has the aim to describe the current concepts of joint preserving and reconstructive surgery in the treatment of the valgus and varus ankle early OA, through an original iconography and clear indications and technical notes.

Dome Supramalleolar Osteotomies for the Treatment of Ankle Pain with Opposing Coronal Plane Deformities Between Ankle and the Lower Limb

BACKGROUND

The dome-type osteotomy is a powerful technique for deformity correction of the limb. However, there is limited information about the utility of dome supramalleolar osteotomy (SMO) in ankle joint preservation surgery. This study aimed to describe the technique and indications for dome SMO in distal tibial malalignment.

METHODS

Twenty-three patients (23 ankles) who underwent dome SMO with a 2-year follow-up were reviewed. Dome SMO was indicated when there were opposing deformities in the ankle and lower limb mechanical axis (ie, varus ankle deformity with valgus lower limb alignment and vice versa) where inherent translation following conventional wedge-type osteotomies could worsen the deformity of the entire lower limb. Patients were divided into 2 groups based on preoperative ankle alignment: the varus ankle group (n = 11) and the valgus ankle group (n = 12). The radiographic correction was assessed using 6 parameters from weightbearing ankle and hindfoot alignment views. In addition, the lower limb mechanical axis was assessed with ankle center deviation (ACD) from the hip-knee (HK) line on the whole limb radiograph, and the weightbearing line (WBL) point was measured to identify changes in the weightbearing load within the ankle joint.

RESULTS

Preoperatively, the varus ankle group had varus ankle deformity (tibiotalar angle [TTA], 76.5 ± 5.8 degrees) with valgus lower limb mechanical axis, whereas the valgus ankle group had valgus ankle deformity (TTA, 99.1 ± 4.5 degrees) with varus lower limb mechanical axis alignment. Postoperatively, a significant improvement in the ankle alignment and the lower limb mechanical axis was observed in both groups. The ACD significantly changed toward the HK line, suggesting an improved lower limb mechanical axis, and the WBL point showed a significant shift of the weightbearing axis toward the uninvolved area within the ankle joint.

CONCLUSION

Dome SMO demonstrated a successful correction of local deformity while simultaneously realigning the hip-knee-ankle axis toward neutral. Additionally, an effective load shifting toward an uninvolved area within the ankle joint was observed.

LEVEL OF EVIDENCE

Level IV, case series.

Joint Preserving Surgery for Valgus Ankle Osteoarthritis

Valgus ankle OA is a complex problem with multiple etiologies that can either be isolated or superimposed on top of other medical or musculoskeletal disorders. Proper medical history, physical, and preoperative radiological examinations are crucial in deciding on surgery and planning the surgical approach. JPS, especially the varisating medial closing-wedge SMOT with solid plate fixation, has been consistently associated with good outcomes for patients with valgus ankle OA. To further improve JPS for valgus ankle OA, further clinical and biomechanical studies are required to address the long-term clinical and functional outcomes and complications.

[Conversion osteotomy for arthrosis of the ankle joint (supramalleolar and inframalleolar)-What can be expected? : Critical review of the literature]

The aim of supramalleolar conversion osteotomy is to reduce the pain of the patient and stop or at least slow down joint degeneration. The indication for supramalleolar osteotomy is asymmetric osteoarthritis of the ankle joint with varus or valgus deformity. Good clinical results for arthritis can be achieved in the early or middle stages. Besides closing and opening wedge osteotomies dome osteotomy is sometimes indicated, especially for larger deformities. The preoperative preparation of individual patient-specific section blocks facilitates the intraoperative implementation and seems to increase the precision. Further studies are necessary to support this. The indications for additional procedures, such as fibular osteotomy are still being discussed. Inframalleolar osteotomy and soft tissue interventions are frequently necessary for balancing the foot.

Bony Procedures for Correction of the Flexible Pediatric Flatfoot Deformity

The pediatric flexible flatfoot is a common foot shape that is most often asymptomatic and may be a physiologic variant of normal. Surgery is only indicated when nonoperative interventions have failed to resolve symptoms. The goal of surgery is to alleviate symptoms by improving hindfoot alignment and restoring the medial arch while preserving joint mobility. This article focuses on the common bony techniques for surgical correction of the pediatric flexible flatfoot that has failed nonoperative management, including calcaneal, midfoot, and supramalleolar osteotomies and distal tibial hemiepiphyseodesis.

Outcomes of Joint Preservation Surgery in Valgus Ankle Arthritis Without Deltoid Ligament Insufficiency

BACKGROUND

To date, information about the role of proximal alignment correction in treating nontraumatic valgus ankle arthritis is limited. This study aimed to report outcomes of realignment surgery, including supramalleolar correction in valgus arthritic ankles without evidence of deltoid ligament insufficiency.

METHODS

Thirteen patients (13 ankles) who underwent joint preservation surgery for valgus ankle arthritis without evidence of deltoid ligament insufficiency were reviewed. Medial opening wedge supramalleolar osteotomy (n = 11) and varization supramalleolar dome osteotomy (n = 2) were performed to realign the hip-knee-ankle-hindfoot axis. Concomitant hindfoot correction was accompanied with either medial displacement calcaneal osteotomy (n = 8) or subtalar arthrodesis (n = 5). Pain, functional outcome (Foot Function Index [FFI]), radiographic arthritis grade (grades 0-4), 9 plain radiographic parameters, and 2 weightbearing computed tomography parameters were evaluated pre- and postoperatively. All patients completed a minimum 2-year follow-up.

RESULTS

Preoperatively, 10 ankles (77%) demonstrated a varus tibial plafond, and 3 ankles (23%) demonstrated a valgus or neutral tibial plafond. Postoperatively, radiographic arthritis grade improved in all except 1 patient, and the mean talar tilt angle improved from 5.5 to 1.7 degrees. The mean pain score (visual analog scale) decreased significantly from 7.3 to 2.5 (P < .05), and the mean FFI improved significantly from 57.7 to 18.6 (P < .001). None of the patients underwent conversion to joint-sacrificing procedures at the latest follow-up.

CONCLUSION

This study demonstrated a possible relationship between lower limb malalignment and valgus ankle arthritis. Realignment surgery, including supramalleolar osteotomies, which straightens the mechanical axis and decreases the slope of the tibial plafond, may be a reasonable approach in joint preservation of valgus ankle arthritis without deltoid ligament insufficiency.

LEVEL OF EVIDENCE

Level IV, case series.

Clinical and Radiographic Results of Ankle Joint Preservation Surgery in Posterior Ankle Arthritis

BACKGROUND

Little information is available about how to manage ankles with eccentric arthritis in the sagittal plane. This study aimed to report clinical and radiographic outcomes following joint preservation surgery for ankles with eccentric arthritis at the posterior tibiotalar joint and a plantarflexed talus in the sagittal plane, which we named posterior ankle arthritis.

METHODS

Ten ankles with posterior ankle arthritis were treated with realignment surgery between 2017 and 2018. Posterior ankle arthritis was defined as having both (1) eccentric narrowing of the joint space at the posterior aspect of the tibiotalar joint on weightbearing lateral radiographs and (2) coronal talar tilt angle less than 4 degrees on weightbearing anteroposterior radiographs. Flatfoot reconstruction with a hindfoot arthrodesis procedure was performed in all patients (subtalar arthrodesis, n = 9; triple arthrodesis, n = 1), and a supramalleolar osteotomy was added in patients with varus distal tibial alignment (n = 6). Pain, functional outcome (foot function index [FFI]), radiographic arthritis stage (stage I to IV), and 9 radiographic parameters, including lateral talar center migration (LTCM), were evaluated on pre- and postoperative weightbearing radiographs. All patients completed a minimum 2-year follow-up.

RESULTS

Preoperative radiographic evaluation demonstrated that ankles with posterior arthritis had a lower medial longitudinal arch, forefoot abduction, and valgus hindfoot alignment. Postoperatively, sagittal tibiotalar alignment was restored, as evidenced by an improved median LTCM from -3.3 to -0.3 mm (P < .001). The radiographic arthritis stage improved in 7 (70%) patients, whereas 3 (30%) remain unchanged in the same stage. The median score for pain (visual analog scale) decreased significantly from 8 to 2, and the median FFI improved significantly from 67.8 to 23.4 (P < .001). None of the patients underwent conversion to joint-sacrificing procedures at the latest follow-up.

CONCLUSION

The study results suggest a possible relationship between posterior ankle arthritis and the plantarflexion of the talus, which can be seen in the setting of a flatfoot deformity. Reconstruction of the flatfoot deformity using subtalar arthrodesis restored the tibiotalar relationship in the sagittal plane and resulted in clinical improvements at an average 2.3-year follow-up in this 10-ankle case series.

LEVEL OF EVIDENCE

Level IV, case series.

Open Ankle Arthrodesis: a Systematic Review of Approaches and Fixation Methods

BACKGROUND

Open ankle arthrodesis (OAA) remains the most widely used operation in end-stage ankle osteoarthritis. However, there is a large variation in terms of approach and fixation methods. The aim of this systematic review was to assess the effect of different approaches and fixation methods on the union rate, complication rate and functional outcome in OAA.

METHODS

A search of the online databases PubMed, Embase, and Cochrane library was performed to identify patients who underwent OAA with screw- and/or plate-fixation.

RESULTS

We identified 38 studies, including 1250 patients (1290 ankles). The union rate was 98% (95% CI 0.95-0.99) for the anterior, 96% (95% CI 0.92-0.98) for the lateral and 96% (95% CI 0.68-1.00) for the combined medial/lateral approach. Screw-fixation achieved an overall union rate of 96% (95% CI 0.93-0.98) and plate-fixation 99% (95% CI 0.96-0.99). The overall complication rate was 14%, 16% and 31% for the anterior, lateral and combined medial/lateral approaches respectively. It stood at 18% for screw-fixation and 9% for plate-fixation. The infection rate was 4%, 6% and 8% for the anterior, lateral and combined approaches respectively. Screw-fixation had an infection rate of 6% and plate-fixation 3%. The postoperative AOFAS scores were 76.8, 76.5 and 67.6 for the anterior, lateral and combined approaches respectively and 74.9 for screw- compared to 78.5 for plate-fixation. These differences did not reach statistical significance.

CONCLUSION

This study, the first of its kind, found little difference in terms of results between approach and fixation method used in OAA.

LEVEL OF EVIDENCE

Level IIa.

3D Assessment in Posttraumatic Ankle Osteoarthritis

BACKGROUND

Auto-generated 3-dimensional (3D) measurements based on weightbearing cone-beam computed tomography (CT) scan technology may allow for a more accurate hind- and midfoot assessment. The current study evaluated the reliability and clinical relevance of such measurements in patients with posttraumatic end-stage ankle osteoarthritis.

METHODS

Seventy-two patients treated at our institution for posttraumatic end-stage ankle osteoarthritis, with available weightbearing conventional radiographs and a cone-beam CT scan, were analyzed. Twenty healthy individuals aged between 40 and 70 years served as controls. Seven variables were measured on weightbearing conventional radiographs (2D) and compared to 3D measurements that were based on reconstructions from weightbearing cone-beam CT scans. The reliability of each measurement was calculated and subgroups formed according to commonly observed deformities.

RESULTS

Inter- and intraobserver reliability was superior for 3D compared to 2D measurements. The accuracy of 3D measurements performed on osteoarthritic ankles was similar to 3D measurements performed on healthy individuals. Thirty-three of the 72 included patients (46%) evidenced an inframalleolar compensation of a supramalleolar/intra-articular ankle deformity (78% = varus compensation; 22% = valgus compensation), whereas 24 of those 72 patients (33%) showed no compensation or a further increase of a supramalleolar/intra-articular ankle deformity (67% = varus deformity; 33% = valgus deformity).

CONCLUSION

Auto-generated 3D measurements of the hind- and midfoot were found to be reliable in both healthy individuals and patients with posttraumatic end-stage ankle osteoarthritis. Such measurements may be crucial for a detailed understanding of the location and extent of hindfoot deformities, possibly impacting decision making in the treatment of end-stage ankle osteoarthritis.

LEVEL OF EVIDENCE

Level III, comparative study.

Hindfoot balancing in total ankle replacement: the role of supramalleolar osteotomies

PURPOSE

To compare the obtained deformity correction and clinical/functional outcomes between patients who underwent total ankle replacement (TAR) with or without a concurrent supramalleolar osteotomy (SMO) to address a varus and/or recurvatum deformity of the distal tibia.

METHODS

Data of 23 patients treated with an additional SMO to correct a varus and/or recurvatum deformity of the distal tibia at the time of TAR were prospectively collected. Twenty-three matched patients who underwent TAR only served as controls.

RESULTS

The American Orthopaedic Foot and Ankle Society (AOFAS)-hindfoot scale and pain assessed on a Visual Analogue Scale (VAS) did not significantly differ between the two groups at the final follow-up (AOFAS-hindfoot scale SMO/TAR group = 82 ± 10; TAR group = 82 ± 12; VAS pain SMO/TAR group = 1 (range, 0-4); TAR group = 1 (range, 0-5)). Ankle range of motion (ROM) did not improve in the SMO/TAR group (pre-operative = 27 ± 13 degrees, last follow-up = 30 ± 9 degrees; P = .294), but did improve in the TAR group (pre-operative = 31 ± 14 degrees, last follow-up = 39 ± 14 degrees; P = .049). Two patients who underwent SMO/TAR showed non-union of the tibial osteotomy, and two patients who underwent TAR only suffered from an intra-operative medial malleolar fracture.

CONCLUSION

An additional SMO during TAR in patients with a varus and/or recurvatum deformity of the distal tibia is not beneficial in most cases and should only be considered in pronounced multiplanar deformities.