The Plumbline: A Novel Radiographic Tool for Assessment of Metatarsus Adductus with Hallux Valgus

Category: Bunion; Midfoot/Forefoot Introduction/Purpose: Metatarsus adductus (MTA) is a complex multiplanar deformity of the foot which has a 30% reported approximate radiographic incidence in patients with symptomatic hallux valgus (HV). Various radiographic angles have been proposed for the assessment of MTA, but these measurements can be complex with a broad range of interrater reliability. We propose a simplistic radiographic assessment method termed the ‘plumbline’ to identify the presence of MTA and to ascertain if enough physical space is available to align the first metatarsal to the longitudinal foot axis via an isolated 1st ray procedure, or if necessary, through a combined approach which also addresses the lesser metatarsals. This method provides a visual reference to determine if a physical blockade to 1st ray correction is present. Methods: The plumbline is assessed on standard weight-bearing AP radiographs. Neutral foot positioning is key as a pronated or supinated clinical position of the foot will impact the alignment of this and other radiographic angular relationships. A transverse midfoot axis line is drawn by identifying and linking two individual points marked at the calcaneocuboid joint and the talonavicular joint. A third point is marked at the distal lateral apex of the medial cuneiform at the first tarsometatarsal joint. A 90° line is subtended from the transverse midfoot axis line, crosses the third point, and extends distally to the 2nd metatarsal head. A positive radiographic plumbline occurs when this line intersects the 2nd metatarsal indicating the need to correct the adducted lesser metatarsal position prior to addressing HV. A negative plumbline remains tangential to the 2nd metatarsal and indicates an isolated HV correction is possible. Results: The metatarsus adductus angle (MAA) measured via Sgarlato's method (SA), and the plumbline were recorded in patients (N=20) scheduled for HV surgery. Initially the cohort was subdivided into subjects deemed to have a normal MAA (SA 15°; N=10). A mean pre-operative MAA measurement of 8.1° (SD 2.3; range 5, 12.1) and 26.5° (SD 4.5; range 19.2, 33.7) were found in these respective subsets. All subjects (100%) with an MAA 15° (N=10) presented with a positive plumbline. The plumbline findings identified when an isolated HV correction would have been possible or impeded based upon 2nd metatarsal position, thus driving the surgical decision making algorithm. Conclusion: The plumbline is used to determine when concomitant MTA and HV correction is beneficial without the need to measure other more traditional radiographic angular relationships. It is a quick and simple method of evaluating the proximity of the metatarsal segments to determine if the first metatarsal is amenable to reduction in isolation or if correction will be limited due to a 2nd metatarsal bone blockade. The visual simplicity of the measurement can also aid in patient education and surgeon satisfaction when describing the surgical approach to this complex three-dimensional anatomic pathology

Hallux Valgus

Hallux valgus is a common condition that results from a complex positional deformity of the first ray. The bunion or medial prominence that results from the lateral deviation and pronation of the hallux is only one component of the 3-dimensional deformity. Hallux valgus can lead to considerable pain and altered joint mechanics. The precise biomechanical etiology remains under debate. Predisposing factors include female sex, age, constricting footwear, and family history. Metatarsus adductus, equinus contracture, hammertoe deformity, and pes planus often coexist with hallux valgus. Nonoperative treatment involves patient education, shoe modifications, toe pads and positioning devices, and activity modifications. Surgery is considered in patients who fail nonoperative treatment with the goal of pain relief, correction of the deformity, improved first ray stability, and improved quality of life. More than 100 different procedures have been described to treat hallux valgus; they include combinations of soft tissue balancing, metatarsal osteotomies, and fusion of either the metatarsophalangeal (MTP) or tarsometatarsal (TMT) joint. The choice of procedures depends on the severity and location of the deformity as well as surgeon preference. Recent advances in operative techniques include minimally invasive surgery and correction of rotational deformity

Primary Endpoint Analysis for a Prospective Multicenter Study Assessing Radiographic Recurrence and Patient Outcomes Following Triplanar Tarsometatarsal Arthrodesis with Early Weightbearing

Category: Bunion; Midfoot/Forefoot Introduction/Purpose: The majority of hallux valgus (HV) corrections have been historically performed via a two-dimensional, transverse plane-focused approach, which has demonstrated high long-term recurrence rates. Recent research demonstrates that 87% of HV deformities are three-dimensional with abnormal frontal-plane rotation of the metatarsal, which cannot be completely addressed with a two-dimensional metatarsal osteotomy alone. While correction at the 1st tarsometatarsal (TMT) joint may provide the optimal surgical approach for 3D anatomic restoration at the apex of the deformity, 1st TMT fusion historically entails an extended period of non-weightbearing. This study evaluated the clinical, radiographic, and patient-reported outcomes in patients undergoing instrumented triplanar 1st TMT arthrodesis (TMTA) with a biplanar plating system and protected near- immediate weightbearing. Methods: A prospective multicenter study that will continue for 60 months post-operatively. Patients 14-58 years old with symptomatic HV (intermetatarsal and HV angles between 10-22° and 16-40°, respectively) and no prior HV surgery on the operative foot were eligible for this study. Patients were treated with an instrumented TMTA procedure using a biplanar plating system with protected early weightbearing. The primary endpoint of this study is radiographic recurrence of HV deformity at 24 months for subjects with successful correction (defined as IMA < 9°, HVA < 15° and TSP ≤ 3 at 6 weeks post-procedure). Recurrence is defined by any two of the three conditions: IMA of ≥12°, HVA ≥20° and TSP ≥4. Secondary outcomes (return to weightbearing and activities, pain measured by visual analog scale (VAS), Manchester-Oxford Foot Questionnaire (MOxFQ), and Patient Reported Outcomes Measurement Information System (PROMIS)) were evaluated post-operatively. Two independent fellowship trained musculoskeletal radiologists reviewed all radiographic data. Results: 173 patients underwent TMTA with mean age of 41.0 (range:14-58) years; 92% females. Median (range) time-to-follow-up is 25 (1.5-49.2) months. Eighteen (10.4%) patients have discontinued. Mean (SD) days to protected weightbearing in CAM boot and return to full work were 8.4 (7.4) and 57.9 (46.2), respectively. At 24 months post-procedure, 99.3% (134/135) of patients were recurrence-free. Statistically significant improvements from baseline in HVA, IMA, and TSP (Table 1), VAS score, MOxFQ and PROMIS domains were observed as early as 6 weeks post-operatively and maintained over time. In 143 patients, mean (95% CI) 24-month improvements were VAS: 3.9 (3.5, 4.2); Walking/Standing (MOxFQ): 39.2 (34.9, 43.4); Physical Function (PROMIS): 9.7 (8.3, 11.2). Nineteen (11.0%) patients experienced hardware complications yet maintained radiographic correction. Conclusion: The results of this study’s primary and secondary endpoints provide supporting evidence that TMTA with biplanar plating is successful in correcting the 3D hallux valgus deformity with early return to weightbearing and low recurrence while demonstrating favorable clinical and patient-reported outcomes. Patients exhibited meaningful pain reduction after surgery and were able to return to full, unrestricted work and activities in less than two months, on average. Statistically significant improvements in patients’ health-related quality-of-life were observed through 36 months, post-operatively. Patients will continue to be followed for up to 60 months with additional evaluations for complications, recurrence, and patient satisfaction

Reconsidering the Broken Homes/Delinquency Relationship and Exploring its Mediating Mechanism

As a result of methodological limitations, prior research may have artificially attenuated the magnitude of the broken homes/delinquency relationship. As a result of theoretical limitations, prior research has achieved only limited success in identifying the mechanism through which broken homes may promote delinquency. The present study addresses both issues using a national probability sample of 1, 725 adolescents. Results suggest that divorce/separation early in the life course may be more strongly related to delinquency than prior research implies and that remarriage during adolescence may be strongly associated with status offending. Overall, results also suggest that association with deviant peers and attitudes favorable to delinquency account for the broken homes/delinquency relationship better than do a number of alternative explanations