Can the Syndesmosis Procedure Prevent Metatarsus Primus Varus and Hallux Valgus Deformity Recurrence? A 5-Year Prospective Study

Radiological Analysis of the Syndesmosis Concept in Metatarsus Primus Varus and Hallux Valgus Deformities Recurrence Prevention

Hallux valgus (HV) is a common deformity of the foot. Its postoperative recurrence is not uncommon and is closely related to the recurrence of its underlying metatarsus primus varus (MPV) deformity. The syndesmosis procedure uses 1 to 2 intermetatarsal cerclage sutures to realign the first metatarsal and then induces a biological bonding between the 2 metatarsals to prevent the MPV deformity from recurring. This radiological study aimed to assess its effectiveness in long-term MPV and HV deformities recurrence prevention. Ninety-two feet of 51 consecutive patients had syndesmosis procedures that were prospectively followed up for more than 1 y and up to 14 y, averaging 100.5 (SD 45.2) months. Patients underwent X-ray examinations regularly at fixed intervals of their feet. We used Hardy's methods in measuring the intermetatarsal angle (IMA), hallux valgus angle (HVA), and medial sesamoid position from standing foot X-rays. More than 450 relevant X-ray and photo images were submitted as Supplementary Material for online viewing and reference. There was a significant final correction of IMA from 14.30° (SD 2.70) to 6.70° (SD 1.75) (p < .0001). There was no significant increase in IMA after the sixth postoperative month to their final follow-up endpoints, regardless of their lengths. There was a significant final correction of HVA from 31.95° (SD 7.45) to 19.1° (SD 7.45) (p < .0001). This study reconfirmed past findings that the MPV deformity could be corrected without osteotomies. Creating a syndesmosis-like intermetatarsal bonding was effective for long-term MPV recurrence prevention. Three feet had postoperative stress fracture of the second metatarsal. However, the HV deformity correction was less satisfactory, and the reasons were explained.

The Syndesmosis Procedure Correction of Hallux Valgus Feet Associated With the Metatarsus Adductus Deformity

Metatarsus adductus and hallux valgus are common foot deformities. Corrective surgery of hallux valgus feet with metatarsus adductus deformity can be challenging and experience a high deformity recurrence rate. The purpose of this study was to demonstrate if the syndesmosis procedure can correct such feet satisfactorily without osteotomies and arthrodesis. 75 hallux valgus feet in 45 patients with a Sgarlato's metatarsal adductus angle ≥15° were studied after having undergone the syndesmosis procedure for an average of 20.22 months. Their average preoperative intermetatarsal angle of 12.56° was improved to 6.00° (p < .001) and metatarsophalangeal angle from 35.61° to 23.46° (p < .001) significantly. Their average American Orthopedic Foot and Ankle Society's clinical scores improved significantly from 56.41 to 90.53 points (p < .001). Fifty-five feet (73.33%) had preoperative metatarsal calluses, and all but 3 had a noticeable reduction in severity. Forty-one patients (91.11%) were able to return to their desired activities and footwear. All relevant raw data formed this study, including x-ray and photographic images, were submitted as Supplementary Material for online viewing and reference. Despite the possible intrinsic rigidity of metatarsus adductus forefoot, this study demonstrated that hallux valgus feet with metatarsus adductus deformity could be corrected anatomically and functionally with the soft tissue syndesmosis procedure and without correcting the preexisting metatarsus adductus deformity. This study also supports the notion that the MA deformity accentuates hallux valgus alignment preoperatively and postoperatively, and possibly all feet in general.

Prevalence and Predisposing Factors for Recurrence after Hallux Valgus Surgery: A Systematic Review and Meta-Analysis

Recurrence is a frequent and undesirable outcome after hallux valgus (HV) surgery. However, the prevalence of HV recurrence and the pre- and postoperatory factors associated with it have not been adequately studied. This study aimed to quantify the prevalence rate of HV recurrence and to analyze its predisposing factors. MEDLINE and EMBASE databases were systematically searched for observational studies including individuals undergoing HV surgical correction. The random-effects restricted maximum likelihood model was used to estimate the pooled effect size (correlation coefficient (r)). Twenty-three studies were included, yielding a total of 2914 individuals. Pooled prevalence of HV recurrence was 24.86% (95% confidence interval (CI), 19.15 to 30.57, I² = 91.92%, p = 0.00). Preoperative HV angle (HVA) (r = 0.29; 95% CI, 0.14 to 0.43) and preoperative intermetatarsal angle (IMA) (r = 0.13; 95% CI, 0.00 to 0.27) showed a moderate positive relationship with recurrence. Postoperative HVA (r = 0.57; 95% CI, 0.21 to 0.94) and sesamoid position (r = 0.46; 95% CI, 0.31 to 0.60) showed strong relationships with recurrence. In conclusion, preoperative HVA, IMA, and postoperative HVA and sesamoid position are significant risk factors for HV recurrence, and the association of these factors with recurrence is affected by age.

The metatarsaus adductus effect by the syndesmosis procedure for hallux valgus correction

Aims

The purpose of this study is to examine the adductus impact on the second metatarsal by the nonosteotomy nonarthrodesis syndesmosis procedure for the hallux valgus deformity correction, and how it would affect the mechanical function of the forefoot in walking. For correcting the metatarsus primus varus deformity of hallux valgus feet, the syndesmosis procedure binds first metatarsal to the second metatarsal with intermetatarsal cerclage sutures.

Methods

We reviewed clinical records of a single surgical practice from its entire 2014 calendar year. In total, 71 patients (121 surgical feet) qualified for the study with a mean follow-up of 20.3 months (SD 6.2). We measured their metatarsus adductus angle with the Sgarlato’s method (SMAA), and the intermetatarsal angle (IMA) and metatarsophalangeal angle (MPA) with Hardy’s mid axial method. We also assessed their American Orthopaedic Foot & Ankle Society (AOFAS) clinical scale score, and photographic and pedobarographic images for clinical function results.

Results

SMAA increased from preoperative 15.9° (SD 4.9°) to 17.2° (5.0°) (p < 0.001). IMA and MPA corrected from 14.6° (SD 3.3°) and 31.9° (SD 8.0°) to 7.2° (SD 2.2°) and 18.8° (SD 6.4°) (p < 0.001), respectively. AOFAS score improved from 66.8 (SD 12.0) to 96.1 (SD 8.0) points (p < 0.001). Overall, 98% (119/121) of feet with preoperative plantar calluses had them disappeared or noticeably subsided, and 93% (113/121) of feet demonstrated pedobarographic medialization of forefoot force in walking. We reported all complications.

Conclusion

This study, for the first time, reported the previously unknown metatarsus adductus side-effect of the syndesmosis procedure. However, it did not compromise function restoration of the forefoot by evidence of our patients' plantar callus and pedobarographic findings.

Level of Clinical Evidence: III

Cite this article: Bone Jt Open 2021;2(3):174–180.

Radiological Evaluation of a Preoperative First Metatarsal Realignment Test for Metatarsus Primus Varus and Hallux Valgus Correction by the Syndesmosis Procedure

BACKGROUND

Metatarsus primus varus correction is one of the primary surgical objectives for hallux valgus correction. Some soft tissue procedures have shown that the first metatarsal can be adequately realigned without osteotomy. The hypothesis of this study was that this correctability should also be demonstrable preoperatively. The purpose of this study was to assess whether a simple forefoot taping technique could do so and whether it could also be correlated with operative results after the syndesmosis procedure.

METHODS

Between May 2014 and December 2015, 147 feet with hallux valgus from 85 patients with an average age of 46.2 years underwent the syndesmosis procedure. All were followed prospectively with standing radiographic assessment of their first intermetatarsal angle, metatarsophalangeal angle, and medial sesamoid position preoperatively without and with a forefoot wrapping technique and postoperatively at 10 days, 6 months, and 1 year.

RESULTS

Their average preoperative intermetatarsal angle was reduced from 14.4 to 8.4 degrees by the wrapping technique, and their average metatarsophalangeal angle was spontaneously reduced from 31.8 to 21.8 degrees. After a minimum 1-year follow-up, they stabilized at 7.4 and 18.6 degrees, respectively. There was significant correlation between hallux valgus and metatarsus primus varus corrections by both forefoot wrapping and surgical methods with Spearman's rank correlation of metatarsophalangeal angle and intermetatarsal angle corrections (r = 0.6077, P < .0001 due to the wrapping method; r = 0.7157, P < .0001 due to the syndesmosis procedure). All raw working radiographic images for this study can be viewed in the Supplemental Material section.

CONCLUSION

This study found that a simple forefoot tape-wrapping technique could be used preoperatively to verify first metatarsal mobility for metatarsus primus varus correction by the soft tissue syndesmosis procedure without osteotomies.

LEVEL OF EVIDENCE

Level II, prospective comparative study.