Stabilization of the subluxed second metatarsophalangeal joint: flexor tendon transfer versus primary repair of the plantar plate

Claw Toe With Dislocated Second Metatarsophalangeal Joint: Treated by Plantar Plate Tenodesis and Release of Collateral Ligaments

Claw toe deformity of the second toe is a common forefoot deformity faced by foot and ankle surgeons. Frequently, it develops as the result of plantar plate insufficiency and subsequent metatarsophalangeal (MTP) joint instability. As the disease deteriorates, the MTP joint can be dislocated. Reduction of the MTP joint without metatarsal osteotomy seems to be a logical approach unless there is excessively long second metatarsal. However, adequate periarticular soft-tissue release including the dorsal capsule, collateral ligaments and extensor tendon is needed to reduce the intra-articular pressure and minimize the risk of joint degeneration. The purpose of this Technical Note is to describe the details of plantar plate tenodesis and release of collateral ligaments for correction of claw second toe associated with dislocation of the metatarsophalangeal joint.

Direct Plantar Approach to Plantar Plate Repair and Associated Wound Complications

BACKGROUND

Lesser toe metatarsophalangeal joint (MTPJ) instability, secondary to plantar plate tear, has been the focus of numerous recent publications, the majority reporting on repair through a dorsal approach. A plantar approach has been described with the advantage of direct ligamentous repair or repair to bone, which follows conventional techniques employed throughout the body. Previous clinical studies have shown success in deformity correction and the longevity of both approaches. The proponents of the dorsal approach advocate that indirect repair of the plantar plate avoids perceived risks of complications with a plantar incision without evidence of superior outcomes. The purpose of this study was to investigate the safety and efficacy of the direct plantar approach to plantar plate repairs (PPRs) by reporting the rate of specific complications in a large clinical series.

METHODS

This was the institutional review board (IRB) approved retrospective study of 204 PPRs in 185 patients (194 lesser MTP, 10 hallux MTP) with an average age of 56 and a mean body mass index (BMI) of 28. Surgical technique involved repair with absorbable braided suture (88%) versus suture anchor (12%) with or without MTPJ pinning (80%). Mean follow up was 53 weeks (range 5-170). Patients were screened for associated risk factors, including diabetes mellitus (8%), tobacco use (5%), neuropathy (1%), and additional concurrent procedures (96%). Complications were defined as superficial or deep infection, painful scars, and reoperation. Analysis was conducted using the Wilcoxon-Mann-Whitney test or Fisher's exact tests for continuous and categorical variables, respectively. Risk factors were analyzed using univariate logistic analysis to produce odds ratios (OR) with a 95% confidence interval (CI) and an inclusion criterion of a P-value, P > .2 for multivariate analysis as determined by Wald tests (significance at P < .05 for final modeling).

RESULTS

Overall, there were 31 total complications (15%) demonstrated by 14 superficial infections (6.8%) and 17 painful scars (8.3%) along with three reoperations (1.4%). All reoperations were performed for deformity or instability, not scar revision. There were no deep infections. No increased odds of complications were found with suture anchor repair, MTPJ pinning, neuropathy, or diabetes. Patients that used tobacco had 7.5 (CI 1.66, 34.06) the odds of developing any wound complication compared with nonsmokers. Tobacco use was also found to significantly increase the odds of superficial infection by 9.8 (CI 2.08, 46.15). There was no increase in painful scars or reoperation in tobacco users. This study did not find an increased complication rate with additional ipsilateral procedures performed at the time of surgery.

CONCLUSION

To our knowledge, this is the largest study evaluating the direct plantar approach to PPR as well as the evaluation of associated complications with the plantar incision. With low complication and minimal reoperation rates, the results of this study have demonstrated the clinical viability of plantar-based incisions. Previous studies have demonstrated the success of PPR and correction of deformity with a direct approach. This case series further demonstrates the safety and efficacy of plantar-based incisions, particularly for direct PPRs.

LEVEL OF EVIDENCE

IV Retrospective Case Series.

CATEGORY

Lesser Toes.

A Critical Biomechanical Evaluation of Foot and Ankle Soft Tissue Repair

The objective of this article is to review the biomechanical stresses that occur during normal physiologic function of lower extremity soft tissue anatomic structures and to use this as a baseline for a critical analysis of the medical literature because it relates to surgical reconstruction following injury. The Achilles tendon, anterior talofibular ligament, plantar plate, and spring ligament are specifically evaluated.

Operative Management: Plantar Plate

The plantar plate is a vital structure for maintaining lesser metatarsophalangeal joint (MPJ) stability. Its primary role is to provide static stabilization of the MPJs, working in conjunction with the long and short flexor and extensor tendons. When insufficiency or attenuation of the plantar plate occurs, a sagittal plane deformity will slowly develop, eventually leading to a "crossover toe" transverse plane deformity. Coughlin coined this descriptive term to describe the later stages of deformity, most commonly affecting the second MPJ. Shortly after, Yu and Judge elaborated on this condition describing it as "predislocation syndrome," an inflammatory condition affecting the plantar plate causing pain and instability, which could progress to subluxation at the MPJ.

Plantar Plate Repair for Metatarsophalangeal Joint Instability of the Lesser Toes

The plantar plate is a known stabilizer of the lesser toe metatarsophalangeal (MTP) joint. MTP instability is a known common cause of metatarsalgia, most commonly in the second toe. In the last decade, clinical staging and anatomic grading mechanisms have been published to guide the surgeons on the treatment of MTP instability; this has also led to an understanding of how plantar plate tears relate to MTP joint instability. Direct surgical repair of the plantar plate has been described, short-term outcomes have been published, and the results are not perfect, but promising with respect to patient satisfaction and pain relief.

Degenerative injuries of the metatarsophalangeal plantar plate on magnetic resonance imaging: a new perspective

Objective

The magnetic resonance imaging diagnostic criteria for a complete tear of metatarsophalangeal plantar plate are well-established. However, more subtle abnormalities can also occur and be a source of pain. The objective of this study is to determine the prevalence of degenerative plantar plate injuries in patients with metatarsalgia who underwent forefoot magnetic resonance imaging and describe the main abnormalities found. The hypothesis is that mild capsular fibrosis will have high sensitivity but low specificity for plantar plate degenerative injuries.

Methods

A retrospective cross-sectional study was conducted with 85 patients (105 feet) with metatarsalgia who underwent forefoot magnetic resonance imaging using a specific protocol to study metatarsophalangeal plantar plate. The experiment observer classified second toe plantar plate as normal, complete rupture or degenerative lesion and described the main magnetic resonance imaging findings.

Results

A normal plantar plate was observed in 75 (71.4%) of the 105 feet assessed, in 25 (24%) feet there were degenerative plantar lesions, and in 5 (4.6%) feet there were complete ruptures. Degenerative injury of the plantar plate was best identified in coronal short axis intermediate-weighted images, with high sensitivity (92%). Pericapsular fibrosis below the intermetatarsal ligament was identified in 96% of cases, with high sensitivity (96%) for diagnosis of degenerative plantar plate injury.

Conclusion

Degenerative lesions of the metatarsophalangeal plantar plate were more prevalent than complete ruptures and were best viewed in coronal short axis intermediate-weighted sequences. Pericapsular fibrosis below the intermetatarsal ligament was the indirect finding most strongly associated with degenerative plantar plate injury.

Lesser Metatarsophalangeal Plantar Plate Repair

Lesser toe plantar plate injuries at the metatarsophalangeal (MTP) joint are a common source of metatarsalgia. Chronic pain with weight-bearing is the common presentation of lesser toe instability. Deformity occurs when the plantar plate is torn or attenuated. Crossover toe and MTP instability often occur with multiplane deformity, most commonly with dorsal contracture of the second toe and medial drift over the Hallux. In this article, the authors present a comprehensive stepwise approach to diagnosing and treating plantar plate injuries using both dorsal and plantar approach techniques.

A versatile method for dorsal-approach plantar plate repair using standard operative instruments

Background

The plantar plate is an important static stabilizer of the lesser metatarsophalangeal joints, and disruptions of the plantar plate can lead to significant instability and lesser toe deformities. In recent years, direct plantar plate repair has been proposed. Although direct repair via a dorsal approach is attractive, a torn plantar plate is small and difficult to access using regular instruments in a restricted operative field.

Methods

In this report, a unique method for plantar plate repairs was used to repair various configurations of plantar plate tears with standard operative instruments that are available in most operating rooms.

Results

Using this method, 10 patients underwent plantar plate repairs, and the mean follow-up period was 24 (range, 14–38) months. The mean visual analog scale score for pain preoperatively was 4.1 (range, 0–6) and decreased to 0.6 (range, 0–3) at last follow-up. Postoperatively, the mean visual analog scale score for satisfaction was 9.6 (range, 8–10) and the mean American Orthopedic Foot and Ankle Society forefoot score was 88.8 (range, 75–100).

Conclusions

Our study proposes an inexpensive and versatile method for plantar plate repair via a dorsal approach that uses standard operative instruments.

Trial registration

ClinicalTrials.gov, NCT04949685. July 2, 2021 - Retrospectively registered,

Level of clinical evidence

4

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04951-w.

Correction of Severe Crossover Toe Deformity By Plantar Plate Tenodesis, Arthroscopic Release of Lumbrical and Plication of Lateral Capsuloligamentous Complex

Plantar plate deficiency is the major cause of instability of the metatarsophalangeal joint, and plantar plate tenodesis can provide dynamic stabilization of the plantar plate. In case of crossover toe deformity, incorporation of arthroscopic release of the medial capsuloligamentous complex and the lumbrical tendon can eliminate the medial deforming force. However, in case of severe deformity, the lateral capsuloligamentous complex is attenuated. The purpose of this Technical Note is to incorporate the technique of arthroscopic plication of the lateral capsuloligamentous complex into the technique of plantar plate tenodesis and arthroscopic release of the medial capsuloligamentous complex and the lumbrical tendon.

Correction of Crossover Toe Deformity by Plantar Plate Tenodesis and Arthroscopic Release of Lumbrical

Plantar plate deficiency is the major cause of instability of the metatarsophalangeal joint. As the joint subluxates dorsally, the lumbrical is tethered on the medial side of the joint by the deep metatarsal ligament and becomes a deforming force for the development of crossover toe deformity. Release of the lumbrical is needed to achieve adequate medial soft-tissue release. Plantar plate tenodesis has been described to correct the deformity by suturing the plantar plate to the extensor digitorum longus tendon. The purpose of this Technical Note is to incorporate the technique of arthroscopic release of the lumbrical tendon into the technique of plantar plate tenodesis.

[Reconstruction of the plantar plate of the metatarsophalangeal joint using a dorsal transarticular approach]

OBJECTIVE

Reconstruction of the plantar plate to stabilize a dislocated or instable lesser metatarsophalangeal joint using a dorsal approach in combination with a Weil osteotomy.

INDICATIONS

Dislocated or instable lesser metatarsophalangeal joint with rupture of the plantar plate.

CONTRAINDICATIONS

Infection, circulatory disorders, symptomatic degenerative arthritis lesser metatarsophalangeal joint.

SURGICAL TECHNIQUE

Weil osteotomy using a dorsal approach. Temporary dislocation of the metatarsal head as proximal as possible. Inspection of the plantar plate. Assessment and classification of type and extent of the rupture. Suturing of the plantar plate to the plantar bases of the proximal phalanx. Fixation of the Weil osteotomy with correction of the metatarsal alignment.

POSTOPERATIVE MANAGEMENT

Weight bearing in a postoperative shoe as tolerated. X‑ray control 6 weeks postoperative. Full weight bearing in a conventional shoe after bony consolidation.

RESULTS

A total of 23 surgical reconstructions of the plantar plate (complete plantar plate repair) between 12/2012 and 10/2014 were performed. The mean follow-up was 18.6 (12-30) months. Five secondary dislocations were observed: one deep postoperative infection, one early dislocation of unknown cause, one secondary dislocation caused by severe hallux valgus recurrence, one massive foreign body reaction to the non-resorbable sutures, and one late secondary dislocation occurred between 6 weeks and 1 year postoperative. Normal function of the reconstructed joint was achieved in 13 of the 23 reconstructions (57%). A reduced toe purchase was observed in 3 reconstructions (13%). A floating-toe resulted after 7 reconstructions (30%).

The Role of Lesser Metatarsophalangeal Joint Arthrodesis for Revision Surgery

Revision hammertoe surgery can be extremely challenging for the foot and ankle surgeon given the scar tissue and available osseous and soft tissue. Although not a common procedure, lesser metatarsophalangeal joint arthrodesis is an option for the patient especially in lieu of an amputation. This article describes the current literature and the surgical technique for a lesser metatarsophalangeal joint arthrodesis.

Outcomes Study of an Innovative Method of Direct Repair of Metatarsophalangeal Joint Instability With an Angiocatheter Needle

Plantar plate tears are a common cause of forefoot pain and digital deformity. Repair of the plantar plate has been described from both a dorsal and plantar approach, each with its own benefits and drawbacks. Many of the approaches use costly devices. Our innovative repair method uses low-cost materials available in most operating room settings. We undertook a retrospective case series study to evaluate outcomes in patients who had undergone plantar plate repair with our method of repair. A review was performed to identify patients with plantar plate disruptions treated with this approach by a single surgeon. Clinical position and patient satisfaction of the involved joints were evaluated. Six patients (9 joints) underwent plantar plate repair using this innovative method and were evaluated at a median follow-up time of 19 (range 19 to 39) months. The mean visual analog scale pain score at final follow up was 0.8 ± 2.0. The median sagittal plane position of the toe was 2 mm (range 0 to 6) from the plantar skin of the digit to the ground. Five of the 6 patients (83%) stated that they would have the procedure again. We were able to obtain satisfactory outcomes with good alignment by repairing the plantar plate with this innovative method. Our data suggest that the described method of plantar plate repair can be used as an effective way to treat metatarsal phalangeal joint instability.

Update on Investigation Methods for Lower Extremity Biomechanics

Imaging with biomechanical analysis augments the clinical examination and improves outcomes by correlating imaging findings with the examination. Plain film radiographs are the gold standard to assess osseous alignment. The biomechanical examination provides information to formulate an accurate assessment. Weightbearing computed tomography scanning is a potentially valuable for functional information about joint biomechanics. True alignment of the lower extremity can be appreciated on weightbearing computed tomography scanning. Soft tissue structures can be assessed with diagnostic ultrasound examination. Acute and chronic injuries that compromise joint stability can be identified.

Plantar Plate Injury and Angular Toe Deformity

Lesser toe plantar plate injuries at the metatarsophalangeal (MTP) joint are a common source of metatarsalgia. The second MTP joint is the most commonly affected digit. The fibrocartilaginous plantar plate is the most important static stabilizer of the MTP joint; high loading with weight bearing can lead to attritional plantar plate injuries. Chronic pain with weight bearing is the common presentation of lesser toe instability. Untreated plantar plate instability can lead to hammer toe and mallet toe deformities. Combined Weil osteotomy and plantar plate repair yields favorable pain relief and angular deformity correction for patients who fail conservative treatment.

A Systematic Review of Plantar Plate Repair in the Management of Lesser Metatarsophalangeal Joint Instability

The plantar plate is a major structure that maintains metatarsophalangeal joint (MTPJ) stability and has only recently gained attention. Anatomic plantar plate repair can directly address the pathologic entity, rather than relying on indirect reduction of the MTPJ instability by osteotomy or tendon transfer techniques. The present report aimed to determine the effectiveness of plantar plate repair for the treatment of patients with lesser MTPJ instability. Different databases were searched using the guidelines in the Cochrane Handbook and recommendations from the Preferred Reporting Items for Systematic reviews and Meta-Analysis statement. Six case series, describing 162 patients who had undergone plantar plate repair in conjunction with either Weil osteotomy or flexor digitorum longus transfer, were retrieved. Favorable outcomes were described in each of the studies included in the present systematic review. However, these results should be interpreted with caution because of the methodologic limitations and biases inherent in the included studies. More rigorous clinical investigations are required to fully understand the effectiveness of plantar plate repair for the management of lesser MTPJ instability.

Lesser Metatarsophalangeal Joint Instability: Treatment with Tendon Transfers

Complex digital deformities and metatarsophalangeal joint instability encompass a wide range of pathology, and we must identify the different degrees of ligamentous disruption. It is important to address a combination of procedures to treat gross deformities of the lesser toes. Surgical treatment should be individualized and requires a sequential process for adequate reduction and deformity correction. There is no gold standard procedure for every deformity. Although residual stiffness can result from tendon transfer, overall patient satisfaction levels remain high when it is performed under the proper indications and concomitantly with other procedures to gain full correction of these challenging deformities.

Modified double plantar plate tenodesis

BACKGROUND

Metatarsophalangeal joint instability of the lesser toe can cause acquired toe deformity. Plantar plate deficiency is the major pathology. Plantar plate repair can stabilize the joint but may result in iatrogenic transverse plane toe deformity in correction of claw toe deformity. Limited toe extension can be resulted after correction of crossover toe deformity by plantar plate tenodesis and extensor digitorum brevis transfer. A modification of the technique is proposed.

MATERIALS AND METHODS

The clinical outcomes of 10 patients with the modified procedure performed were assessed.

RESULTS

The correction was full in all toes with no recurrence.

CONCLUSION

The modified technique can stabilize the metatarsophalangeal joint and correct lesser toe deformity without the need of tendon transfer, osteotomy or sophisticated instrumentation.

Metatarsalgia

The causes of metatarsalgia are classified as primary, secondary, and iatrogenic. Anatomical and biomechanical considerations separate "static" from "propulsive" forms of metatarsalgia. The physical examination should be combined with an assessment of weight-bearing radiographs and, if needed, of ultrasound or magnetic resonance imaging scans. The first-line treatment is conservative (stretching exercises, footwear modification, insoles, and lesion debridement). Soft-tissue surgical procedures (gastrocnemius muscle recession, tendon transfer, and plantar plate repair) should also be considered. Among the various types of metatarsal osteotomy, the Weil procedure is reliable. Percutaneous methods are being developed but require evaluation. A treatment algorithm can be developed based on whether the hallux is normal or abnormal. Metatarsalgia due to inflammatory disease requires a specific treatment strategy.

Plantar Plate Repair Using a Direct Plantar Approach: An Outcomes Analysis

Direct plantar plate repair using a plantar approach has been described previously, but with few reports of the outcomes or clinical results. The purpose of the present study was to determine the outcomes of this technique. We performed a retrospective analysis of patients who had undergone direct plantar plate repair with or without concomitant Weil osteotomy and a prospective patient-reported subjective outcomes analysis. Ultimately, 131 patients (144 toes) were included, and the response rate for the mailed surveys was 53.5% (77 of 144 toes). The clinical outcomes reported a well-aligned toe in 87.1% of cases, with a recurrence rate of 7.6% (11 of 144) and a revision rate of 2.8% (4 of 144). Statistically significant improvement in the overall modified Foot Function Index (p < .001) and subscale scores for pain (p < .001), disability (p < .001), and activity limitation (p = .001) were noted postoperatively compared with the preoperative data. The median postoperative visual analog pain scale level reported at survey completion was 2.0 (range 0.0 to 10.0; mean ± standard deviation 2.3 ± 2.6). Despite the modified Foot Function Index scores, the patient satisfaction questionnaire data reported mixed results. Our modified Foot Function Index results demonstrated that this approach provides excellent postoperative pain relief, improvement of associated disability, and improvement in activity limitations. The importance of managing patient expectations is acknowledged secondary to the discrepancy with the patient satisfaction data and the modified Foot Function Index results. Further prospective study is warranted to compare this technique with alternate dorsal approaches for plantar plate repair with and without associated commercially available suture passing systems.

Role of magnetic resonance imaging versus ultrasound for detection of plantar plate tear

BACKGROUND

Plantar plate tears could be the reason of forefoot pain, affecting foot function. Magnetic resonance imaging (MRI) and ultrasound (US) were commonly used for the diagnosis of plantar plate tears. The decision of whether to use MRI or US carried some controversy. Our study aimed to find out the diagnostic accuracy of MRI versus US for plantar plate tears.

METHODS

The database of the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE, and relative orthopedic meetings until May 2016 were searched. Studies involved in the diagnostic detection of MRI or ultrasound for plantar plate tears with surgical criteria as the reference test were included. Data was analyzed by meta-analysis. We compared sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and summary receiver operating characteristic (sROC) plot of both MRI and US.

RESULTS

Seven studies involving 246 plantar plate tears were included. The MRI showed more diagnostic accuracy than US for the detection of plantar plate tears. The sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of MRI were 95%, 54%, 2.08, and 0.08, respectively, while the same values for US were 93%, 33%, 1.20, and 0.35, respectively. And the sROC showed more superior diagnostic accuracy than the US.

CONCLUSION

The current result suggests that MRI has better accuracy than US for detection of plantar plate tears.

Interdigital Neuroma in the Second Intermetatarsal Space Associated with Metatarsophalangeal Joint Instability

The entrapment theory is the most commonly accepted theory concerning the development of interdigital neuroma; it incriminates the deep transverse metatarsal ligament as the major causative factor of the condition. This report presents a patient with interdigital neuroma in the second intermetatarsal space, which was strongly suspected to be caused by the metatarsophalangeal joint instability due to plantar plate injury. Surgical intervention revealed that the neuroma was located more distally and dorsally than the deep transverse metatarsal ligament and was pinched between the adjacent metatarsal heads, suggesting the involvement of the metatarsophalangeal joint instability and chronic trauma as etiologies in this case.

Correction of Crossover Toe Deformity by Arthroscopically Assisted Plantar Plate Tenodesis

Plantar plate deficiency is the major pathology causing metatarsophalangeal joint instability. As the joint subluxates dorsally, the lumbrical is tethered at the medial side of the joint by the deep metatarsal ligament and becomes a deforming force for the development of crossover toe deformity. Plantar plate repair or reconstruction is a logical surgical treatment option. This can be performed through a dorsal or plantar approach. The purpose of this technical note is to report a minimally invasive technique of crossover toe deformity correction by suturing the plantar plate to the extensor tendon. It is indicated for symptomatic crossover toe deformity that is not responsive to nonsurgical treatment. It is contraindicated if the metatarsophalangeal joint is degenerated, destructed, or dislocated, or there is interdigital neuroma at the sides of the deformed toe, or the deformity is caused by bony deformities of the metatarsal head or the proximal phalanx.

Evaluation of lesser metatarsophalangeal joint plantar plate tears with contrast-enhanced and fat-suppressed MRI

OBJECTIVE

To present findings of plantar plate (PP) lesions from MRI with administration of gadolinium and to differentiate PP lesions from others causes of metatarsalgia.

MATERIALS AND METHODS

Two musculoskeletal radiologists reviewed 249 contrast-enhanced forefoot MRI scans from patients with metatarsalgia between June 2012 and June 2013. Evaluations focused on hyper-vascularized/fibrous tissue and other findings associated with PP tears.

RESULTS

Fifty-nine patients had PP tears, 59 % were female. Most of these patients, 48/59 (81.4 %), had a single metatarsophalangeal (MTP) PP lesion in one foot, although 7/59 patients had one lesion in each foot, 3/59 (5.1 %) had two in one foot, and 1/59 (1.7 %) had three lesions in one foot. The second MTP joint was the most common location for PP tears (n = 56), followed by the third (n = 12) and fourth (n = 3) MTP joints. Lateral (n = 33) and full thickness (n = 28) PP lesions were the most frequent, and central (n = 3) and lateral/central (n = 7) tears were less prevalent. Fifty (70.5 %) PP lesions showed pericapsular fibrosis in pre-contrast sequences, and 21 (29.5 %) were visible only after administration of gadolinium. All PP lesions had collateral ligament involvement. Others findings included interosseous tendon lesions (n = 29), interosseous tendon rupture (n = 29), synovitis (n = 49), flexor tenosynovitis (n = 28), crossover toe (n = 2), hammertoe (n = 1), intermetatarsal space (IS) neuromas (n = 11), and third IS neuromas (n = 12).

CONCLUSION

PP tears are a common cause of metatarsalgia, accounting for more than 20 % of cases in our sample. A substantial portion of the lesions (29.5 %) became visible only after the administration of gadolinium.

Tendon Transfers for Management of Digital and Lesser Metatarsophalangeal Joint Deformities

Managing digital and metatarsophalangeal joint (MTPJ) deformities can range from simple to complex and uniplanar to triplanar. Because of the complexity and variability of digital and MTPJ deformities, there are many procedures, and no 1 procedure has become the gold standard. Tendon transfers for digital and MTPJ deformities are just 1 treatment option, and usually they are not stand-alone procedures. Typically, a combination of procedures needs to be performed. This article describes the surgical technique and provides a review of the literature, including clinical results for tendon transfers of the central rays.

Plantar plate radiofrequency and Weil osteotomy for subtle metatarsophalangeal joint instablity

Background

To the present day, literature has only discussed how to treat extensive plantar plate and collateral ligament lesions, with gross joint subluxation and obvious clinical instability. The treatment options for early stages of the disease with minor injuries and subtle instabilities have not been described. The main purpose of this prospective study is to evaluate the efficacy of the combination of the arthroscopic radiofrequency shrinkage and distal Weil osteotomy in the treatment of subtle metatarsophalangeal joint instability.

Method

Prospective data (clinical, radiological, and arthroscopic findings) of 19 patients, with a total of 35 slightly unstable joints, was collected. The physical examination defined the hypothesis for plantar plate lesions (grades 0 and 1), which was confirmed during the diagnostic step of the arthroscopic procedure.

Results

Among our patients, 73 % were females and 63 % reported wearing high heels. The average age was 59 years and post-operative follow-up was 20 months. In the initial sample frame, 62 % of joints showed spread-out toes with increased interdigital spacing. The mean American Orthopedic Foot and Ankle Society score rose from 53 points pre-operatively to 92 points post-operatively and a visual-analog pain scale average value of eight points pre-operatively decreased to zero post-operatively. During the pre-operative evaluation, none of the patients had stable joints and over 97 % were classified as having grade 1 instability (<50 % subluxation). After treatment, 83 % of the joints became stable (degree of instability 0) and over 97 % were congruent. All studied parameters showed statistically significant improvements in the post-operative period (p < 0.001) showing the efficiency of the treatment in pain relief, while restoring the joint stability and congruity.

Conclusion

Arthroscopic radiofrequency shrinkage in combination with distal Weil osteotomy promotes functional improvement, pain relief, and restores the joint stability in the plantar plate lesion grades 0 and 1.

Surgical reduction and ligament reconstruction for chronic dorsal dislocation of the lesser metatarsophalangeal joint associated with hallux valgus

BACKGROUND

Hallux valgus (HV) is occasionally associated with chronic dislocation of the lesser metatarsophalangeal (MTP) joints. We have developed a novel surgical procedure to treat dislocation of the lesser MTP joints. This study aimed to describe our procedure and investigate the outcomes of surgical intervention in the treatment of HV with dislocation of the lesser MTP joints.

METHODS

Twenty-three patients (27 feet, average age: 63.6 years, average follow-up: 49.5 months; a minimum follow-up of 24 months) underwent surgical intervention for HV and dislocation of the lesser MTP joints. Twenty-three feet had dislocation (10 feet) or subluxation (13 feet) of the second MTP joint, whereas 4 feet had dislocation of the second and third MTP joints. The surgical procedure included a distal soft-tissue procedure combined with proximal osteotomy for correction of the HV, and reconstruction of the collateral ligaments (CL) following open reduction with complete release of the capsule and the CL at the metatarsal head for dislocation of the lesser MTP joints. Outcomes were assessed using the Japanese Society for Surgery of the Foot (JSSF) scale and radiological examinations.

RESULTS

The JSSF score improved significantly from an average of 49.7 points preoperatively to 93.1 points postoperatively. The average HV angle and intermetatarsal angle decreased significantly from 44.6° and 18.1° preoperatively to 7.9° and 6.0° postoperatively, respectively. The average extension and flexion of the second MTP joint was 53.1° and 13.8° at the most recent follow-up, respectively. Postoperatively, no feet had dislocation of the second or third MTP joint, three had subluxation of the second MTP joint, and one had subluxation of the third MTP joint. Osteoarthritis of the lesser MTP joint had developed in two feet (7.4 %) at the time of the most recent follow-up.

CONCLUSION

Our surgical procedure achieved significant correction of HV, a low rate of postoperative re-dislocation of the lesser MTP joints, and significant improvement of pain and function for symptomatic moderate-to-severe HV with dislocation of the lesser MTP joints.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Technique Tip: The Use of McGlamry Elevator to Assist Suture Passing in the Dorsal Technique of Plantar Plate Repair With Weil Osteotomy for Lesser Metatarsophalangeal Joint Instability

The combination of a dorsal approach to the plantar plate with a Weil's metatarsal osteotomy has been shown to provide an adequate exposure for plantar plate repair. However, soft tissues in a restricted area of the metatarsophalangeal joint could present as a technical difficulty during suture retrieval during repair of the plantar plate. The purpose of this article is to describe the use of the McGlamry elevator for assistance in the retrieval of sutures through the proximal phalanx.

LEVEL OF EVIDENCE

Level V: Expert opinion.

Exposure via sequential release of the metatarsophalangeal joint for plantar plate repair through a dorsal approach without an intraarticular osteotomy

BACKGROUND

Traditionally, plantar plate repairs have been performed from either a direct plantar approach or through a dorsal approach utilizing an intraarticular metatarsal osteotomy. It is unknown if a plantar plate repair can be reliably performed through a dorsal approach without an osteotomy.

METHODS

The second through fourth metatarsal phalangeal (MTP) joints of 4 fresh frozen cadavers were sequentially dissected and the exposure of the plantar plate was quantified with a digital micrometer. A suture passer was then utilized to pass a suture through the released plantar plate without a metatarsal osteotomy.

RESULTS

The mean plantar plate exposure after capsulotomy was 1.1 mm, after capsulotomy and release of the collateral ligaments exposure was 2.5 mm, after the addition of a release of plantar structures with a McGlamry elevator exposure was 4.1 mm, and after the addition of a plantar plate takedown the exposure was 5.3 mm. Every specimen had a minimum of 4 mm of exposure. Two sutures were successfully passed through every plantar plate with the exposure obtained.

CONCLUSION

Significant improvement in exposure of the plantar plate was achieved with each successive structure released .

CLINICAL RELEVANCE

Successful plantar plate repair can be reliably performed through a dorsal approach without a metatarsal osteotomy in a cadaveric model.

Extensor apparatus of the lesser toes: anatomy with clinical implications--topical review

Lesser toe deformities are one of the most common conditions faced by orthopedic surgeons. Knowledge of the anatomy of the lesser toes is important for ensuring correct diagnosis and treatment of deformities, which are caused by factors such as muscle imbalance between the extensor apparatus and flexor tendons. However, this apparatus has not received sufficient attention in the literature. In addition, the large number of inaccurate and erroneous descriptions means that gaining an understanding of these structures is problematic. The objective of the present article is to clarify the anatomy of the extensor apparatus by means of a pictorial essay, in which the structures involved will be grouped and discussed in detail. The most relevant clinical implications will be addressed.

LEVEL OF EVIDENCE

Level V, expert opinion.

Prospective evaluation of protocol for surgical treatment of lesser MTP joint plantar plate tears

BACKGROUND

Instability of the lesser metatarsophalangeal (MTP) joints is a common cause of deformity and pain. The purpose of this study was to prospectively evaluate the surgical outcomes for the different grades of plantar plate tears and propose a treatment protocol.

METHODS

Sixty-eight patients (100 MTP joints) were prospectively enrolled and graded according to the anatomical grade system for plantar plate tears. Based on this classification, the appropriate surgical procedure was chosen as follows: grades 0 and I, thermal shrinkage with radiofrequency; grades II and III, direct reinsertion of the plantar plate; and grade IV, flexor-to-extensor tendon transfer. All surgical procedures were associated with a Weil metatarsal osteotomy. Evaluations were performed before and after surgical treatment with a mean follow-up of 2 years (12-36 months), using clinical and radiological parameters: American Orthopaedic Foot and Ankle Society (AOFAS) Lesser MTP-IF Scale, visual analog scale (VAS), ground touch, joint stability, and toe purchase.

RESULTS

The analysis of the clinical parameters demonstrated a significant improvement of all groups (P < .0001) after surgical treatment, but grade IV had less VAS improvement and a fair AOFAS average score (72 points). All groups improved regarding physical examination parameters, but grade I, III, and IV tears had proportionally less stable MTP joints following surgery, as well as a lower proportion of normal postoperative toe purchase and ground touch. All groups showed a significant improvement regarding radiographic parameters.

CONCLUSION

All groups of operatively treated patients had significant improvement with regard to subjective and objective parameters. Grades I, III, and IV presented inferior results compared with grades 0 and II.

LEVEL OF EVIDENCE

Level IV, case series.

Etiology and management of lesser toe metatarsophalangeal joint instability

The terms crossover toe and lesser metatarsophalangeal joint instability both describe a deterioration of the soft tissue structures that give stability to the lesser MTP joints. Initial treatment regimens focused on indirect repair of the instability without addressing the primary pathology. A staging system of the clinical examination and a grading system of the surgical findings are now available to help surgeons classify and treat the plantar plate insufficiency. Improved imaging techniques and direct surgical repair techniques through a dorsal approach have changed the treatment and possibly the results of this difficult condition.

Metatarsophalangeal joint instability of the lesser toes and plantar plate deficiency

Our understanding of lesser toe metatarsophalangeal joint instability has increased substantially over the past few decades. Some recent articles on the subject have provided detailed anatomic descriptions that help to characterize the primary stabilizing structures of the joint. Some surgeons now advocate the incorporation of a primary repair of the plantar plate into the surgical plan for correction of metatarsophalangeal joint deviation in the sagittal and transverse planes. New surgical techniques have been developed to expose, inspect, and reliably repair the plantar plate, if necessary. Dorsal and plantar approaches have both been used successfully to repair the plantar plate. Tears of the plantar plate can be repaired primarily or advanced on the base of the proximal phalanx through bone tunnels. Outcomes of these procedures are promising, with improvements in pain and function reported along with sustained deformity correction.

The direct plantar plate repair technique

Lesser metatarsophalangeal (MTP) joint instability is a common and painful condition that can severely limit activity and recreation. Synovitis and joint effusion may be seen early on with progression of instability to encompass predislocation and eventual complete dislocation of the MTP joint. Various surgical techniques have been described to treat lesser MTP joint instability and associated hammertoe deformities. Many surgeons experience frustration with the surgical outcome of metatarsal osteotomies and flexor transfers commonly used for this condition. The plantar plate apparatus is felt to be at the heart of the pathomechanics of this condition in many instances and is often misunderstood or even overlooked. Indirect dorsal approaches to plantar plate repair often require reliance on complex instrumentation and provide a limited view of the involved structures. The authors describe a direct plantar approach technique for plantar plate repair with realignment of the lesser MTP joint and hammertoe pathologies.

Role of plantar plate and surgical reconstruction techniques on static stability of lesser metatarsophalangeal joints: a biomechanical study

BACKGROUND

Disruption of the plantar plate of the lesser metatarsophalangeal (MTP) joints leads to significant instability. Despite the fact that plantar plate disorders are common, the best mode of treatment remains controversial with operative treatments having variable and somewhat unpredictable clinical outcomes.

METHODS

Lesser MTP joints from the second, third, and fourth toes from fresh-frozen cadaver feet were biomechanically tested: (1) intact, (2) with the plantar plate disrupted, and (3) following a Weil osteotomy, a flexor-to-extensor tendon transfer, or a Weil osteotomy with a subsequent flexor-to-extensor tendon transfer with testing in superior subluxation, dorsiflexion, and plantarflexion.

RESULTS

The plantar plate significantly contributed to stabilizing the sagittal plane of the lesser MTP joints. The flexor-to-extensor tendon transfer significantly stabilized the disrupted lesser MTP joints in both superior subluxation and in dorsiflexion. The flexor-to-extensor tendon transfer following a Weil osteotomy also significantly stabilized the disrupted lesser MTP joints in both superior subluxation and in dorsiflexion.

CONCLUSIONS

In this cadaver-based experiment, disruption of the plantar plate of the lesser MTP joints led to significant instability. After plantar plate disruption, the Weil osteotomy left the joint unstable. The flexor-to-extensor tendon transfer by itself increased the stability of the joint in dorsiflexion, but combined with a Weil osteotomy restored near intact stability against superior subluxation and dorsiflexion forces.

CLINICAL RELEVANCE

Surgeons using the Weil osteotomy for plantar plate deficient MTP joints may consider adding a flexor tendon transfer to the procedure. Techniques to repair the torn plantar plate directly are needed.

Ultrasound imaging for diagnosis of plantar plate ruptures of the lesser metatarsophalangeal joints: a retrospective case series

Tears of the plantar plate can be a source of significant forefoot pain, leading to alterations of foot function and gait. The objective of the present retrospective study was to further determine the value of ultrasound imaging in diagnosing plantar plate tears after clinical evaluation through a comparison of the ultrasound and intraoperative examination findings. Eight patients were identified who had undergone surgical intervention for a painful lesser metatarsophalangeal joint after ultrasound examination to diagnose a plantar plate pathologic entity. The intraoperative examination findings were used to calculate the sensitivity, specificity, and positive and negative predictive values of ultrasound in the diagnosis of plantar plate tears. The sensitivity and specificity of the ultrasound examination was 1 and 0.6, respectively. The positive and negative predictive value was 0.6 and 1, respectively. An ultrasound examination in the diagnosis of lesser metatarsophalangeal joint plantar plate tears displayed comparable sensitivity in identifying the pathologic features when compared with magnetic resonance imaging, with considerably less financial cost for the examination.

Second metatarsophalangeal joint pathology and freiberg disease

Pain in the second metatarsophalangeal joint (MTPJ) is a complaint frequently encountered by foot and ankle specialists. The pathology associated with this joint is often painful and debilitating for the patient. In the past, typical treatment protocols for second MTPJ pathology were aimed at relief of patient symptoms. Conservative treatment and offloading devices have historically dominated treatment options for the clinician. However, recent surgical techniques and procedures have been developed to correct the mechanical and structural defects that can affect this joint. The aim of this review was to outline recent developments and treatment options for common second MTPJ pathologies.

Metatarsophalangeal joint instability of the lesser toes

Metatarsophalangeal joint instability of the lesser toes is a common finding and a common cause of metatarsalgia. The clinical presentation can include swelling without digital deformity; however, often, this can progress to the development of coronal and transverse plane malalignment. In some cases, frank metatarsophalangeal joint dislocation can develop. The treatment regimen has historically focused on indirect surgical realignment using soft tissue release, soft tissue reefing, tendon transfers, and periarticular osteotomies. An improved understanding of the plantar plate has recently led to the development of a clinical staging system and surgical grading system of plantar plate attenuation. A dorsal surgical approach, using a Weil osteotomy, allows the surgeon to directly access and repair or advance the plantar plate to the base of the proximal phalanx. The addition of direct plantar plate repair could be a significant advancement in the reconstruction and realignment of metatarsophalangeal joint instability.

MRI evaluation of the MTP plantar plates compared with arthroscopic findings: a prospective study

BACKGROUND

Instability of the lesser metatarsophalangeal (MTP) joints has been widely reported and plantar plate insufficiency is a key part of this pathologic process. The diagnosis is made clinically but can be aided by imaging studies, particularly magnetic resonance imaging (MRI); however, the sensitivity and accuracy of this method compared to direct visualization of these lesions has not yet been established, nor has interobserver accuracy of MRI been assessed for evaluation of plantar plate pathology. In this study, our goals were to identify the accuracy of the MRI in describing plantar plate tears when compared to direct arthroscopic visualization using an anatomic grading system and to test the influence of an anatomic grading system in the accuracy of the MRI readings.

METHODS

We evaluated the clinical exam, MRI scans, and arthroscopic findings of 35 patients with lesser MTP instability.

RESULTS

Using an anatomic grading system, a distinct improvement in the radiological evaluation and interpretation occurred. Knowledge of the pattern of plantar plate tears by a radiologist enabled them to locate and describe the type of tears of the plantar plate on the MRI. The amount of training and the experience of the radiologist were also important factors in our study. The senior radiologists had much better levels of accuracy (Group A, 77.0%; Group B, 88.5%) than less experienced radiologists.

CONCLUSION

Prior knowledge of the pathophysiology and morphological types of lesions of the plantar plates was helpful for accurate identification and description of the tears by the radiologist.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

Treatment of dynamic claw toe deformity flexor digitorum brevis tendon transfer to interosseous and lumbrical muscles: a literature survey

The authors report the results of a literature survey of corrective surgical treatment based on FDL and FDB tendon transfer for dynamic claw toe deformities. The study revealed that FDL transfer was first described in 1967 by Malcolm A. Brahms in "Common Foot Problems", and FDB transfer was first mentioned in 1993 in the first edition of the treatise by G. Pisani "Trattato di Chirurgia del Piede". The paper also discusses the functional effect of FDB transfer, compared to FDL transfer.

Stability of the metatarsophalangeal joint of the lesser toes: a cadaveric study

Dorsal instability of the metatarsophalangeal joint (MTPJ) of the lesser toes is an important cause of forefoot pain. Both conservative and surgical treatment options have been proposed. However, the role of each static stabilizing structure has not been elucidated. We hypothesized that isolated sectioning of the plantar plate (PP) would result in greater dorsal translation compared to isolated sectioning of the medial collateral ligaments (MCL) or lateral (LCL) collateral ligaments, or the extensor hood (EH), and that combined injury to two or more structures would result in greater dorsal translation compared to isolated PP injury. Fifty-four cadaveric lesser toe specimens were randomized into groups for individual and combined sectioning of the PP, EH, and LCL and MCL. A 30 N axial load was applied to each specimen in the plantar-dorsal direction and dorsal translation of the phalanx was measured for each condition. ANOVA was used to compare groups. A 19% change in MTP translation was found from intact after sectioning the PP. No significant difference in translation was seen after individual sectioning of the EH, MCL, or LCL. A significant increase in translation occurred from intact with the following sectioning combinations: MCL + LCL, 37%; EH + MCL + LCL, 45%; and PP + MCL + LCL, 63%. Thus, the PP is the main restraint for dorsal MTPJ translation. MCL and LCL have important partial contribution to MTPJ stability. Injury to the PP, individually, or combined injuries to the PP, EH, MCL, or LCL, appear to cause significant instability that may warrant more aggressive treatment.

Role of collateral ligaments in metatarsophalangeal stability: a cadaver study

BACKGROUND

Lesser metatarsophalangeal joint (MTPJ) instability is a common complaint. The role each of the collateral structures play in maintaining joint stability is unknown.

METHODS

Twenty-six fresh-frozen cadaver lesser MTPJ's were tested for instability with the amount of force necessary to translate the joint 3 mm dorsally. Specimens were tested with 1) intact collateral ligaments, 2) transected accessory collateral or proper collateral ligaments (ACL or PCL), 3) repaired ACL or PCL, 4) transected ACL and PCL, 5) repaired ACL and PCL, and 6) transferred interosseous (IO) tendon. Student t-tests were performed to test for statistical significance (p value less than 0.05).

RESULTS

The mean force required for 3 mm of dorsal displacement was 25 ± 13 N (range, 11 to 52 N) in the 26 specimens. Transecting either the ACL alone or the ACL and PCL led to the most instability versus transecting the PCL alone. Repairing both ligaments improved stability. The IO tendon transfer was comparable to the direct repair of the PCL but was inferior to the direct repair of the ACL.

CONCLUSION

Both ACL and PCL have a stabilizing effect on the MTPJ. However, the ACL was more important since primary transection of the ACL led to more instability and additional transection of the PCL in an ACL deficient model did not lead to significantly more instability.

CLINICAL RELEVANCE

Direct repairs of both structures improved the stability of the joint but not back to normal. IO tendon transfer is a possible adjunct to collateral ligament repairs, but in itself is not sufficient to restore stability.

Pull-out technique for plantar plate repair of the metatarsophalangeal joint

Plantar plate rupture is a common cause of forefoot pain, multiplanar malalignment, subluxation, or dislocation of the metatarsophalangeal joint (MTPJ). The treatments that have been described for MTPJ instability of lesser toes include amputation, lengthening and/or tendon transfer, periarticular soft-tissue release (capsule, collateral ligaments, and plantar plate), colateral ligament reconstruction, metatarsal shortening osteotomy, and suture of plantar plate lesion. This article outlines the anatomy, pathogenesis, and diagnosis of plantar plate rupture, and describes a new technique that combines joint decompression by Weil osteotomy with a plantar plate repair using a pull-out technique.

Lesser metatarsophalangeal instability: presentation, management, and outcomes

BACKGROUND

Lesser metatarsophalangeal (MTP) instability is a common cause of forefoot pain. In this prospective study, we looked at its presentation, management and outcome.

METHODS

We studied characteristics of patients presenting to a specialist foot and ankle clinic with lesser MTP instability. We used the drawer test to diagnose and stage instability. Patients were followed up in clinic or by telephone interview.

RESULTS

We identified 154 patients with lesser MTP instability; 127 (82%) were female, median age was 56 years. One foot was affected in 107 patients (69%). The second toe only was affected in 99 patients (64%) and multiple toes in 52 (34%) but always involving the second toe if multiple toes involved. 150 toes (52%) had Grade 1 instability, 108 (37%) Grade 2 and 21 (7%) Grade 3 instability. Twelve toes (4%) presented dislocated. Ninety nine patients (64%) were treated nonoperatively, using functional taping, shoe modifications, and injections. Fifty five patients (36%) were treated operatively, including lesser toe straightening, flexor-extensor transfer, Weil and Stainsby procedures. At followup, the mean AOFAS score and standard deviation was 69 ± 16.3 for the nonoperative group compared to 67 ± 17.8 in the operative group. The mean pain score and standard deviation was 31 mm ± 23.7 mm for the nonoperative group and 23 mm ± 24.1 mm in the operative group. Thirty-nine patients (52%) were either satisfied or very satisfied with treatment in the nonoperative group compared to 31 patients (66%) in the operative group. None of these differences were statistically significant.

CONCLUSION

Painful MTP instability is a common cause of forefoot pain. Most patients can be treated nonoperatively. Operatively treated patients had no significant improvement in outcomes with regards to pain or function.

Fifth toe plantar plate repair in a professional soccer player: case report

Level of Evidence: V, Expert Opinion