Lateral release in hallux valgus deformity: from anatomic study to surgical tip

A Joy-Stick Assistant Three-Dimensional Modified Technique of Minimally Invasive Surgery for Mild or Moderate Hallux Valgus

BACKGROUND

Minimally invasive surgery (MIS) such as minimally invasive chevron osteotomy and Akin osteotomy (MICA) has become popular in the treatment of hallux valgus. However, how to correct three-dimensional deformities in hallux valgus effectively and simply in MICA is still difficult. Special equipment is required in MICA as has been reported before. It is meaningful and necessary to reduce the reliance on special equipment in MICA.

METHODS

From January 2021 to July 2022, patients with mild or moderate hallux valgus were treated with a joy-stick assistant three-dimensional modified technique (Joy-stick 3D technique) of MIS. VAS, AOFAS Hallux MTP-IP scores, hallux valgus angle (HVA), intermetatarsal angle (IMA), and distal metatarsal articular angle (DMAA) were measured pre- and postoperatively at the last follow-up of at least 6 months. Scores and radiologic angles were compared using paired sample t-test.

RESULTS

A total of 36 cases were included. HVA, IMA, and DMAA were (22.3 ± 6.1)°, (14.0 ± 3.2)°, and (8.9 ± 3.2)° preoperatively, and decreased to (7.0 ± 1.8)°, (3.7 ± 1.0)°, and (3.3 ± 1.1)° postoperatively. VAS decreased from 4.3 ± 1.7 to 0.7 ± 0.7. AOFAS Hallux MTP-IP scores improved from 68.6 ± 7.6 to 92.9 ± 6.1. Comparing mild and moderate cases, though HVA, IMA, and DMAA were significantly different preoperatively, the angles became statistically similar after surgery.

CONCLUSIONS

A joy-stick assistant three-dimensional modified technique is proposed to control the three-dimensional position of the metatarsal head and to reduce dependence on special tools. Mild and moderate hallux valgus deformities are effectively corrected using Joy-stick 3D technique.

Clinical guideline on the third generation minimally invasive surgery for hallux valgus

Minimally invasive surgery for hallux valgus correction, has been attracting great interests in the recent decades, due to the potential benefits of less pain, decreased recovery times, smaller scars with better cosmesis, and improved early post-operative range of motion. The most recent developments in minimally invasive surgery have evolved into the third generation with modifications of the chevron-type osteotomy. This evidence-based clinical guideline of the third generation minimally invasive surgery for hallux valgus is initiated and developed collectively by the Foot and Ankle Committee of Orthopedic Branch of Chinese Medical Doctor Association, Foot and Ankle Committee of Sports Medicine Branch of Chinese Medical Doctor Association, and Foot and Ankle Expert Committee of Orthopedic Branch of the Chinese Association of the Integrative Medicine. This clinical guideline provides recommendations for indications, contraindications, operative planning and techniques, post-operative management, management of complications, and prognosis of the third generation minimally invasive surgery for hallux valgus. The Translational Potential of this Article This comprehensive guideline aims to establish standardized recommendations for the indications, contraindications, operative techniques, and post-operative management of the third generation minimally invasive surgery for hallux valgus. By adhering to this guideline, the success rate of the procedure could be maximized. This comprehensive guideline serves as a valuable reference for practitioners interested in or preparing to perform minimally invasive surgery for hallux valgus.

Percutaneous hallux valgus surgery: Anatomical study of its safety and effectiveness

BACKGROUND AND HYPOTHESIS

Although percutaneous hallux valgus surgery is increasing in popularity, concerns about safety regarding neurovascular and tendinous structures remain. The first aim of this body-donor study was to evaluate the safety of three common percutaneous portals. Secondly, to evaluate percutaneous surgery effectiveness in completing adductor tendon release and first ray osteotomies.

PATIENTS AND METHODS

Twenty body-donor feet were included and underwent three percutaneous procedures, which are commonly performed in combination: distal metatarsal osteotomy, proximal phalanx osteotomy and adductor tendon release. After surgery, the distance between surgical portals and relevant neurovascular structures was measured. Damage to this neurovascular structures, tendons or articular cartilage was noted. Completion of adductor tendon release and osteotomies was verified.

RESULTS

The medial dorsal digital nerve of the hallux was damaged in two specimens. Mild peritendon damage was observed in two feet. The rest of neurovascular and tendinous structures were intact. No cartilage damage was observed. The distance between the adductor tenotomy portal and the lateral dorsal digital nerve of the hallux and the first dorsal metatarsal artery was 3.3mm (SD 1.4) and 2.4mm (SD 1.8), respectively. Complete adductor tenotomy was achieved in 14 feet.

CONCLUSIONS

The structure with the highest risk of damage during percutaneous hallux valgus surgery is the medial dorsal digital nerve. The lateral dorsal digital nerve and the first dorsal metatarsal artery might be at risk due to the small distance to the adductor tendon release portal. A deep anatomical knowledge and a meticulous surgical technique are required to avoid lesions to neurovascular and tendinous structures.

LEVEL OF EVIDENCE

V, Cadaveric study.

How Adductor Hallucis Reattachment Affects Outcomes Following Scarf Osteotomy in Hallux Valgus Correction: A 4- to 8-Year Follow-Up Retrospective Comparative Study

This study observed the differences between 2 adductor hallucis release techniques (nonreattachment vs reattachment) in 4- to 8-year follow-up outcomes of scarf osteotomy combined with distal soft tissue release (DSTR) in moderate to severe hallux valgus correction. A retrospective review of moderate to severe hallux valgus patients treated with scarf osteotomy with DSTR was conducted. The patients were divided into 2 groups based on adductor hallucis release techniques (without and with reattachment to the metatarsophalangeal joint capsule). The demographic-matching process divided the samples into 27 patients per group. A comparison of last follow-up of clinical foot ankle ability measure (FAAM) for activity of daily living (ADL) and numerical rating scale for pain during 2 hours of ADL and radiographic outcomes (hallux valgus angle (HVA) and intermetatarsal angle (IMA) was analyzed. A p < .05 was considered a statistically significant difference. The final follow-up of FAAM for ADL was statistically better in the reattachment group as the median was 79.0 (IQR = 4.00) versus 76.0 (IQR = 4.00), p = .047. However, this difference did not achieve minimal clinical importance difference (MCID). The last follow-up of IMA was also statistically better in the reattachment group as the mean was 7.67 (SD = 3.10) versus 10.5 (SD = 3.59), p = .003. DSTR with adductor hallucis reattachment has statistically better IMA correction and maintenance than nonreattachment for moderate to severe hallux valgus correction using scarf osteotomy at 4- to 8-years follow-up. However, the better clinical outcomes did not achieve MCID.

Role of lateral soft tissue release in percutaneous hallux valgus surgery: a systematic review and meta-analysis of the literature

BACKGROUND

It is unclear whether lateral soft tissue release (LSTR) is required as part of percutaneous hallux valgus (PHV) surgery. The primary aim of this systematic review was to assess whether LSTR reduces the risk of recurrence of hallux valgus deformity. The secondary aims were to assess if LSTR increases the risk of complications, improves the clinical outcome and leads to a greater radiographic correction.

METHODS

We performed a PRISMA-compliant PROSPERO-registered systematic review, pooling clinical papers reporting results after PHV surgery into two categories (PHV with (Group 1, G1) and without LSTR (Group 2, G2)) and comparing them. Data regarding the study design, demographics, the surgical procedure and the clinical and radiological outcome were extracted and compared. Risk of bias was assessed using the modified Coleman Methodology Score (mCMS).

RESULTS

Sixteen studies were selected (G1:594 feet; G2:553 feet). The pooled proportion of recurrence at a minimum 21-month follow-up (2%, 95%CI 0-3 vs 2%, 95%CI 0-5; p = 0.70) did not differ in the two groups. Similarly, the pooled proportion of complications (27%, 95%CI 17-38 vs 25%, 95%CI 12-37; p = 0.79) was similar. The pre- (p = 0.23) and post-operative AOFAS scores (p = 0.16), the pre-(HVA: p = 0.23) (IMA: p = 0.94) and post-operative radiological angles (HVA: p = 0.47) (IMA: p = 0.2) and the methodological quality of studies (p = 0.2) did not differ either between G1 and G2.

CONCLUSION

There is no evidence that LSTR performed during percutaneous HV surgery reduces the risk of recurrence of the deformity at a mean 4-year follow-up nor improves the clinical and radiological outcome.

LEVEL OF EVIDENCE

Level IV systematic review of Level I to IV studies.

Comparison of modified U-shaped and inverted L-shaped medial capsulorrhaphy in hallux valgus surgery: a prospective, randomized controlled trial of 75 patients

PURPOSE

The purpose of this study was to report a modified U-shaped medial capsulorrhaphy and compare its clinical and radiological differences with an inverted L-shaped capsulorrhaphy in hallux valgus (HV) surgery.

METHODS

A prospective study of 78 patients was performed between January 2018 and October 2021. All patients underwent chevron osteotomy and soft tissue procedures for HV, and the patients were randomly separated into 2 groups according to the medial capsule closing techniques: a modified U-shaped capsulorrhaphy (group U) and an L-shaped capsulorrhaphy (group L). All patients were followed for at least a year. The preoperative and follow-up data were collected for each patient and included patient demographics, weight-bearing radiographs of the foot, the active range of motion (ROM) of the first metatarsophalangeal (MTP) joint and the American Orthopedic Foot and Ankle Society (AOFAS) forefoot score. Mann-Whitney U test was used for the comparison of the postoperative measures between the groups.

RESULTS

In total, 75 patients with 80 affected feet met the inclusion criteria, with 38 patients (41 feet) in group U and 37 patients (39 feet) in group L. One year after surgery, the mean hallux valgus angle (HVA), intermetatarsal angle (IMA), and AOFAS score in group U improved from 29.5 to 7.1, from 13.4 to 7.1, and from 53.4 to 85.5, respectively. The mean HVA, IMA, and AOFAS score in group L improved from 31.2 to 9.6, from 13.5 to 7.9, and from 52.3 to 86.6, respectively. Comparing the 1-year postoperative measures between the 2 groups, a significant difference was found in HVA (P = 0.02), but not found in IMA and AOFAS score (P = 0.25 and P = 0.24, respectively). The mean ROM of the first MTP joint was 66.3 degrees preoperatively and 53.3 degrees at the 1-year follow-up in group U, while 63.3 and 47.5 in group L. The degrees of ROM after 1 year in group U were better than those in group L (P = 0.04).

CONCLUSION

Compared to the inverted L-shaped capsulorrhaphy, the modified U-shaped capsulorrhaphy provided a better ROM of the first MTP joint; at 1 year following surgery, the modified U-shaped capsulorrhaphy maintained the normal HVA better.

Modified scarf osteotomy for hallux valgus: From a finite element model to clinical results

PURPOSE

Finite element (FE) analysis and clinical follow-up were used to evaluate the efficacy of modified scarf osteotomy for moderate-to-severe hallux valgus (HV).

METHOD

We retrospectively evaluated 42 patients (44 feet) who underwent modified rotational scarf osteotomy for moderate-to-severe HV at our institution between January 2010 and January 2019. Radiological indicators and subjective scores were recorded at different time points. To compare the results and elemental characteristics, a FE model of the metatarsophalangeal (MTP) joint that included anatomically realistic geometrical and structural characteristics was built. The biomechanical features and correction differences in dynamic loads as well as the incidence of troughing were estimated.

RESULTS

Both the hallux valgus angle (HVA) and intermetatarsal angle (IMA) showed significant improvement 6 weeks postoperatively (p < 0.05); additionally, the HVA increased from 6 weeks postoperatively to the last follow-up, while the IMA showed no significant changes (p > 0.05). The subjective scores significantly improved from the preoperative period to the last follow-up. The percentages of troughing and recurrence were remarkably low in our pilot study because of the innate stability of the modified rotated fixation.

CONCLUSION

Our preliminary findings suggest that modified rotational scarf osteotomy offers sufficient stability, correct HV deformity effectively, and good clinical outcomes for moderate to severe HV.

Iatrogenic Damage to Neurovascular and Soft Tissue Structures During Lateral Release of Hallux Valgus: A Comparative Anatomical Study of Minimally Invasive Versus Open Surgical Techniques

Lateral release is often an integral step in surgical correction of hallux valgus and can be performed using open or minimally invasive techniques. We investigated whether these techniques cause iatrogenic damage to arteries, nerves, tendons, or joint capsules. In this cadaver study, lateral release was performed on 9 pairs of specimens by a specialized foot surgeon. The specimens were randomly assigned to each group. The operations were followed by anatomical preparation, data collection, photo documentation, and statistical analysis. Iatrogenic damage to arteries, nerves, tendons, or joint capsules was rare, regardless of the surgical technique used. However, with the minimally invasive technique, the tendon of the extensor hallucis longus muscle and the sensitive terminal branches of the fibular nerve were at risk due to their anatomical proximity to the access portal. The deep transverse metatarsal ligament was potentially at risk if the adductor hallucis muscle was completely detached from the lateral sesamoid. When the deep transverse metatarsal ligament was transected there was risk of damaging the underlying plantar neurovascular structures. Both surgical techniques are safe in terms of the risk of injury to neighboring neurovascular and soft tissue structures.

The Correction Potential of the Lateral Release of the Hallux Valgus: A Comparative Anatomical Study of Minimally Invasive Versus Open Surgical Technique Using a Dorsal Approach

Background

Lateral release (LR) is an integral part of surgical correction of hallux valgus. A comparison was made between the open and minimally invasive LR techniques using a dorsal approach. The reliability and safety of the two methods were compared. Besides, the release of specific structures was investigated with special emphasis on ascertaining if the release was partial or a total one.

Methods

In this study on cadavers, LR was performed on nine pairs of foot and ankle specimens. The group assignments were randomized for each case. The operations were followed by anatomical preparation, data collection, photo documentation, and statistical analysis.

Results

A statistically significant advantage was observed with the open dorsal approach as there was a complete release of the adductor hallucis muscle from the lateral sesamoid and the lateral metatarsosesamoid ligament (p = 0.015 in each case). In terms of releasing the adductor hallucis muscle from the proximal phalanx, the lateral joint capsule, and the lateral collateral ligament, none of the investigated procedures showed better performance. However, open dorsal access tends to show a higher degree of release more frequently.

Conclusions

Splitting of the lateral joint capsule, including the lateral collateral ligament and lateral metatarsosesamoid ligament via the dorsal approach can be performed reliably and completely using the open surgical technique. The open dorsal technique shows better rates of detachment when the adductor hallucis muscle is released from the lateral sesamoid. Both techniques resulted in incomplete release of the adductor hallucis muscle from the proximal phalanx.

Study Type

Therapeutic-investigating the results of a treatment.

Level of Evidence

II (Prospective cohort study).

Supplementary Information

The online version contains supplementary material available at 10.1007/s43465-021-00575-3.

Correction Power of Percutaneous Adductor Tendon Release (PATR) for the Treatment of Hallux Valgus: A Cadaveric Study

Osteotomies are commonly used in order to correct hallux valgus deformity. However, soft tissue structures also play an essential role in the etiology, progression, and treatment of hallux valgus (HV). The purpose of the present study was to analyze the correcting power (varus), reduction strength (sesamoid) and rotation of metatarsal and proximal phalanx after percutaneous adductor tendon release (PATR). To date, no study addresses this issue. Eleven cadaveric fresh-frozen below-the-knee cadaveric lower limbs with associated hallux valgus deformity were used. These specimens were subjected to a constant abduction force after PATR. HV and intermetatarsal angles showed statistically significant differences when comparing the preoperative and postoperative periods. PATR showed to be a reliable technique as the adductor tendon was completely released in 9 cases, and 75% released in the remaining 2 feet. The study supports that PATR provides powerful and quantifiable correction of HV deformity and can be accurately performed percutaneously.

The success rate of first metatarsophalangeal joint lateral soft tissue release through a medial transarticular approach: A cadaveric study

BACKGROUND

The objective of this study was to evaluate the success rate of first metatarsophalangeal joint (MTPJ) lateral soft tissue release through a medial transarticular approach.

METHODS

Ten cadaveric specimens were used (6 females/4 males, mean age, 73.4years). Lateral release was performed through a 4cm medial approach using a number 15 blade. Surgical aim was to release four specific structures: lateral capsule, lateral collateral ligament (LCL), adductor hallucis tendon (AHT) and lateral metatarsosesamoid suspensory ligament (LMSL). Once completed, a dissection of the first intermetatarsal space was performed. Success rate was graded in accordance to the number of structures successfully released: 0% (no structures), 25% (1/4), 50% (2/4), 75% (3/4) and 100% (4/4). Inadvertent injuries to other soft tissue structures were recorded.

RESULTS

The success rate for lateral soft tissue release was 100% in 7 cadaveric specimens, and respectively 75%, 50% and 25% in the other 3 specimens. The LCL was successfully released in all specimens. The lateral joint capsule, AHT and LMSL were released in 80% of the specimens. Chondral damage to the first metatarsal head, unintended release of the conjoined tendon and lateral head of the flexor hallucis brevis (FHB) occurred respectively in 40%, 50% and 20% of the specimens.

CONCLUSIONS

Our cadaveric study demonstrated high success rate in the release of specific lateral soft tissue structures of the first MTPJ through a medial transarticular approach. Inadvertent release of the lateral head of the FHB, conjoined tendon and iatrogenic chondral damage of the first metatarsal head are complications to be considered.

LEVEL OF EVIDENCE

Cadaveric study - Level V.

A meta-analysis of comparative clinical studies of isolated osteotomy versus osteotomy with lateral soft tissue release in treating hallux valgus

BACKGROUND

Contradictory results have been reported in the literature over the beneficial effect of the lateral soft tissue release (LSTR) when associated to an osteotomy for the treatment of hallux valgus (HV).

MATERIALS AND METHODS

Six comparative studies totalizing 425 patients (549 feet) were computed and comparing two groups: one group of patients having osteotomy alone and the other group having osteotomy with LSTR.

RESULTS

Subgroup analysis in relation to the type of LSTR yielded significant better HVA correction (P<0.0001) in favor of those reporting the release of the lateral sesamoido-metatarsal ligament (LSML). A moderate significance (P=0.03) of the inter-metatarsal angle (IMA) difference was found in favor of LSTR.

CONCLUSIONS

There could be a beneficial effect of transecting LSML in all cases of HV deformity, and a probable efficacy of an added adductor hallucis tendon transection when the deformity is moderate to severe.

Single incision lateral release for hallux valgus using a cervical biopsy blade: A cadaveric study

The role of lateral release is widely accepted and regarded as a key step in the management of hallux valgus. There remains however debate in the literature in regards to which structures should be divided and the method of approach. As such, a technique of lateral release using a curved blade placed inferior to the metatarsal head to divide the lateral metatarsosesamoid suspensory ligament and incise the lateral joint capsule has been developed. This technique was performed on fourteen fresh frozen cadaveric specimens which were then dissected. In all cases the lateral metatarsosesamoid suspensory ligament was divided and the lateral capsule incised to the joint line. One case of iatrogenic injury to the oblique head of adductor hallucis tendon was noted. No cases of neurovascular injury were noted. The authors conclude that this method of lateral release to be safe and reproducible in a cadaveric model in achieving lateral release for the management of hallux valgus.

[Soft tissue techniques in hallux valgus surgery]

The hallux valgus represents combined bony and soft tissue pathology. In addition to known bony surgical procedures, addressing the soft tissue with regard to the anatomical structures, the surgical technique and the extent of correction are discussed.The goal of the operation is the restoration of the physiological balance between the active and passive stabilizing factors of the MTP-I-joint. The joint capsule, the ligaments and the tendons of the first ray act directly as stabilizing structures, whereas the hind foot and the position of the upper ankle have an indirect influence on the MTP-I-joint.The present work gives an overview of the pathoanatomy of the MTP-I-joint in the hallux valgus pathology. The individual anatomical structures are presented with regard to their physiological and pathological influence and the possible therapeutic options.

Consensus on Surgical Management of Hallux Valgus from China

Hallux valgus deformity is one of the most common diseases in foot and ankle surgery. Satisfactory outcomes tend to be achieved only through operative correction. However, selection of the optimal surgical strategy is always a controversial topic, and the rate of dissatisfied patients postoperativelyis still very high. It is well known that there are various pathological changes in hallux valgus deformity, so it is impossible to use one specific procedure to solve all the problems. It requires a careful preoperative physical examination and radiographic assessment to choose the best operation for each kind of deformity according to each pathalogical change, combined with good postoperative dressing, immobilization and proper rehabilitation and follow up, to improve surgical outcomes and reduce postoperative rate of complication and dissatisfaction. In order to achieve these goals, a Consensus on the Operative Correction of Hallux Valgus has been developed by the Foot and Ankle Working Committee, Orthopaedic Branch, Chinese Association of Orthopaedic Surgeons. Foot and ankle surgeons following this consensus must be fully aware of their patients' desires, carefully evaluate different pathological processes and clinical symptoms and be skilled in various procedures. Then these procedures can be easily selected, converted and combined based on preoperative plans and intraoperative conditions.

A New Measure of Tibial Sesamoid Position in Hallux Valgus in Relation to the Coronal Rotation of the First Metatarsal in CT Scans

BACKGROUND

We aimed to find a new radiographic measurement for evaluating first metatarsal pronation and sesamoid position in hallux valgus (HV) deformity.

METHODS

Data from a clinical study of 19 control patients (19 feet) with no HV deformity were compared with preoperative data of 138 patients (166 feet) with HV deformities. Using a weightbearing plain radiograph in anteroposterior (AP) view, the intermetatarsal angles (IMAs) and the hallux valgus angles (HVAs) of the control and study groups were measured. Using a semi-weightbearing coronal computed tomography (CT) axial view, the α angle was measured in the control and study groups. In addition, the tibial sesamoid grades in plain radiograph tangential view and the CT axial view were measured. The tibial sesamoid position in an AP view was checked preoperatively. Based on these measurements, 4 types of HV deformities were defined.

RESULTS

The mean values of the α angle in the control and HV deformity groups (control group µ = 13.8 degrees, study group µ = 21.9 degrees) was significantly different. Among 166 HV feet, 145 feet (87.3%) had an α angle of more than 15.8 degrees, which is the upper value of the 95% confidence interval of the control group, indicating the existence of abnormal first metatarsal pronation in HV deformity. Four types of HV deformities were defined based on their α angles and tibial sesamoid grades in CT axial view (CT 4 position). Among 25.9% (43/166) of the study group, abnormal first metatarsal pronation with an absence of sesamoid deviation from its articular facet was observed. The prominent characteristic of this group was that they had high grades in the AP 7 position (≥5); however, in the CT 4 position, their grade was 0. This group was defined as the "pseudo-sesamoid subluxation" group.

CONCLUSIONS

Patients with HV deformities had a more pronated first metatarsal than the control group, with a greater α angle. Pseudo-subluxation of the sesamoids existed in 25.9% of our study group. From our results, we suggest that the use of the CT axial view in assessments of HV deformity may benefit surgeons when they make operative choices to correct these deformities. With regard to the pseudo-sesamoid subluxation group, the use of the distal soft tissue procedure is not surgically recommended.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

[Distal soft-tissue procedure in hallux valgus deformity]

OBJECTIVE

Distal, lateral soft tissue release to restore mediolateral balance of the first metatarsophalangeal (MTP) joint in hallux valgus deformity. Incision of the adductor hallucis tendon from the fibular sesamoid, the lateral capsule, the lateral collateral ligament, and the lateral metatarsosesamoid ligament.

INDICATIONS

Hallux valgus deformities or recurrent hallux valgus deformities with an incongruent MTP joint.

CONTRAINDICATIONS

General medical contraindications to surgical interventions. Painful stiffness of the MTP joint, osteonecrosis, congruent joint. Relative contraindications: connective tissue diseases (Marfan syndrome, Ehler-Danlos syndrome).

SURGICAL TECHNIQUE

Longitudinal, dorsal incision in the first intermetatarsal web space between the first and second MTP joint. Blunt dissection and identification of the adductor hallucis tendon. Release of the adductor tendon from the fibular sesamoid. Incision of the lateral capsule, the lateral collateral ligament, and the lateral metatarsosesamoid ligament.

POSTOPERATIVE MANAGEMENT

Postoperative management depends on bony correction. In joint-preserving procedures, dressing for 3 weeks in corrected position. Subsequently hallux valgus orthosis at night and a toe spreader for a further 3 months. Passive mobilization of the first MTP joint. Postoperative weight-bearing according to the osteotomy.

RESULTS

A total of 31 patients with isolated hallux valgus deformity underwent surgery with a Chevron and Akin osteotomy and a distal medial and lateral soft tissue balancing. The mean preoperative intermetatarsal (IMA) angle was 12.3° (range 11-15°); the hallux valgus (HV) angle was 28.2° (25-36°). The mean follow-up was 16.4 months (range 12-22 months). The mean postoperative IMA correction ranged between 2 and 7° (mean 5.2°); the mean HV correction was 15.5° (range 9-21°). In all, 29 patients (93%) were satisfied or very satisfied with the postoperative outcome, while 2 patients (7%) were not satisfied due to one delayed wound healing and one recurrent hallux valgus deformity. There were no infections, clinical and radiological signs of avascular necrosis of the metatarsal head, overcorrection with hallux varus deformity, or significant stiffness of the first MTP joint.

Distal soft tissue procedure in hallux valgus surgery: biomechanical background and technique

The distal soft tissue procedure has evolved into an indispensable additional surgical procedure to increase the corrective effect in hallux valgus surgery. Considering the biomechanical development of hallux valgus deformity, degenerative changes of the soft tissues around the first metatarsophalangeal joint contribute much more to the deformity than changes in the bony structures which can rather be seen as degenerative changes secondary to the deformity. Thus the principles in hallux valgus correction should aim to reverse all pathogenetic steps leading to deformity: release of the contracted lateral soft tissue structures, tightening of the torn-out medial structures and reduction and rebalancing the first metatarsal head onto the sesamoid complex. The scientific discussion over the last decades has clarified the impact of different surgical steps and methods on the efficacy of the lateral release, the risk of creating overcorrection or instability of the joint and the risk of avascular necrosis of the first metatarsal head. According to anatomical and clinical data, a lateral soft tissue release can be combined with a distal metatarsal osteotomy, provided that the osteotomy is performed in a defined safe zone without increasing the risk for avascular necrosis of the first metatarsal head. Transecting the lateral metatarsosesamoid suspensory ligament is the key to a successful lateral release in hallux valgus surgery. Release of the deep transverse metatarsal ligament and the adductor hallucis muscle does not contribute to hallux valgus correction. The lateral short sesamophalangeal ligament and the plantar attachment of the articular capsule should be preserved to avoid possible joint instability. Thus today, the distal soft tissue procedure cannot be seen only as a supplementary surgical procedure in cases where the bony procedure needs additional correction, but rather is an indispensable procedure to restore the physiological situation and function of the first metatarsophalangeal joint.