Partial retention of the acetabular cement mantle in aseptic revision hip arthroplasty: is it a viable option?

INTRODUCTION: Choosing the most appropriate reconstruction method when addressing a cemented cup at hip revision surgery can be a difficult decision. The aim of this study is to look into the practice and results of retaining a well-fixed medial acetabular cement mantle while removing loose superolateral cement. This practice goes against a preconceived principle that if some of the cement is loose it must all be removed. So far, no significant series looking at this is available in the literature. METHODS: We assessed a cohort of 27 patients in our institution where this practice was carried out and assessed their outcomes clinically and radiographically. RESULTS: Of the 27 patients, 24 had follow-up ⩾2 years (2.9-17.8, mean 9.3 years). There was 1 subsequent revision for aseptic loosening at 11.9 years, 1 first-stage revision of both stem and cup for infection at 1 month, and 2 patients died without a 2-year review. 2 patients did not have radiographs available for review. 2 of the 22 patients with radiographs available had changes in lucent lines, which were not clinically significant. CONCLUSION: Based on these results we conclude that retaining well-fixed medial cement during socket revision is a viable reconstruction option in carefully selected cases.

Mind the gap! The Lucent Line Sign: A Pathognomonic Radiographic Finding in Periprosthetic Hip Fractures Around Cemented Polished Tapered Femoral Stems.

BACKGROUND: Diagnosing minimally displaced femoral PPFs using plain-film radiographs can be challenging. As a result, fractures can be missed. CASE REPORT: We present four cases of minimally displaced PPFs around cemented polished tapered stems. In each case, radiographs demonstrate no clear cortical breach, but the presence of a fracture is highlighted by a pathognomic lucent line between the cement mantle and the prosthesis: The Lucent Line Sign. CONCLUSION: Paying attention to the Lucent Line Sign can be pivotal in the diagnosis of minimally displaced PPFs around cemented polished tapered stems.

B2 or not B2? That is the question: a review of periprosthetic fractures around cemented taper-slip femoral components.

AIMS: Periprosthetic fractures (PPFs) around cemented taper-slip femoral prostheses often result in a femoral component that is loose at the prosthesis-cement interface, but where the cement-bone interface remains well-fixed and bone stock is good. We aim to understand how best to classify and manage these fractures by using a modification of the Vancouver classification. METHODS: We reviewed 87 PPFs. Each was a first episode of fracture around a cemented femoral component, where surgical management consisted of revision surgery. Data regarding initial injury, intraoperative findings, and management were prospectively collected. Patient records and serial radiographs were reviewed to determine fracture classification, whether the bone cement was well fixed (B2W) or loose (B2L), and time to fracture union following treatment. RESULTS: In total, 47 B2W fractures (54.0%) and one B3 fracture (1.1%) had cement that remained well-fixed at the cement-bone interface. These cases were treated with cement-in-cement (CinC) revision arthroplasty. Overall, 43 fractures with follow-up united, and two patients sustained further fractures secondary to nonunion and required further revision surgery. A total of 19 B2L fractures (21.8%) and 19 B3 fractures (21.8%) had cement that was loose at the cement-bone interface. These cases were managed by revision arthroplasty with either cemented or uncemented femoral components, or proximal femoral arthroplasty. One case could not be classified. CONCLUSION: We endorse a modification of the original Vancouver system to include a subclassification of B2 fractures around cemented femoral prostheses to include B2W (where cement is well-fixed to bone) and B2L (where the cement is loose). Fractures around taper-slip design stems are more likely to fracture in a B2W pattern compared to fractures around composite beam design stems which are more likely to fracture in a B2L pattern. B2W fractures can reliably be managed with CinC revision. Cite this article: Bone Joint J 2021;103-B(1):71-78.

Comparative Study of Spring Ligament Reconstructions Using Either Hamstring Allograft or Synthetic Ligament Augmentation.

BACKGROUND: Idiopathic flatfeet are usually caused by attenuation of the medial soft tissues rather than a lateral osseous deficiency. Debate continues on whether spring ligament attenuation or posterior tibial tendon (PTT) dysfunction is the initial driver for the deformity. Our comparative prospective study aimed to quantify the radiological and clinical outcomes of 2 techniques for spring ligament reconstruction using a hamstring graft or a synthetic ligament. METHODS: Seventeen spring ligament reconstructions (SLRs) were performed in 17 patients using synthetic ligament augmentation and 16 SLRs were performed using hamstring allograft in 13 patients. Additional procedures such as gastrocnemius recession, PTT advancement, flexor digitorum longus transfer, and calcaneal osteotomy were performed as required. A minimum of 12 months of follow-up was available for all cases. Radiographic analysis was performed with standardized parameters. RESULTS: Following SLR with synthetic ligament augmentation, all radiological parameters significantly improved (P < .05). Hamstring allograft SLR also demonstrated significantly improved radiographic parameters in all but Meary's line at final follow-up. At 12 months, patient outcome scores were significantly better in the synthetic ligament group. CONCLUSION: Reconstruction of the spring ligament using either hamstring allograft or synthetic ligament augmentation provided significant improvements in radiological alignment; however, superior patient-reported outcomes were found in the synthetic ligament augmentation group. LEVELS OF EVIDENCE: Level III, retrospective cohort study.

Anatomy of the Lateral Plantar Ligaments of the Transverse Metatarsal Arch.

BACKGROUND: While the anatomy of the Lisfranc complex is well understood, the lateral tarsometatarsal ligamentous structures, in contrast, are less well studied. Our aim in this study was to identify an anatomical explanation as to why the second to fifth metatarsals function as a unit in homolateral and divergent midfoot injuries. METHODS: Eleven cadaveric lower limbs, preserved in formaldehyde, were examined at the University of Liverpool Human Anatomy and Resource Centre. Each of the lower limbs was dissected to identify the plantar aspect of the transverse metatarsal arch. RESULTS: On removal of the long plantar ligament, the peroneal longus tendon was visible, as was its insertion onto the first metatarsal base. A lateral Lisfranc ligament (which was a transverse suspensory metatarsal ligament) spanned between the bases of the second and fifth metatarsals in all specimens with an average length of 33.7 mm and width of 4.6 mm. This ligament has not previously been described. It was noted that in all specimens, the long plantar ligament blended with the lateral Lisfranc ligament. In addition to the lateral Lisfranc ligament, separate intermetatarsal ligaments were identifiable connecting each metatarsal. The long plantar ligament provided a connection through the lateral Lisfranc ligament connecting the transverse and longitudinal arches of the foot. CONCLUSION: We found a plantar ligament that provided connection through the long plantar ligament of both the transverse and the longitudinal arches. It spanned from the second to the fifth metatarsal, which we believe may explain that in some cases, lateral instability can be overcome when the middle column is stabilized. CLINICAL RELEVANCE: We suspect that in the majority of homolateral and divergent types of tarsometatarsal injuries that the lateral Lisfranc ligament remains intact and thus it has significant clinical ramifications.

An Anatomic Study of the Naviculocuneiform Ligament and Its Possible Role Maintaining the Medial Longitudinal Arch.

BACKGROUND:: Weight-bearing radiographic analysis of pes planus deformities show, with varying degree of severity, a break in the Meary line. The break in the Meary line occurs not only at the talonavicular joint but also distal to the spring ligament and reported tibialis posterior insertion. Our aim in this study was to investigate the distal plantar ligaments of the medial longitudinal arch, to try to identify other areas where deformity correction could be affected. METHODS:: We examined 11 cadaveric lower limbs that had been preserved for dissection in a solution of formaldehyde. The lower limbs were carefully dissected to identify the plantar aspect of the medial longitudinal arch. RESULTS:: In all specimens, the tibialis posterior tendon inserted into the plantar medial aspect of the navicular with separate slips to the intermediate and lateral cuneiform. The navicular cuneiform ligament extended from the navicular to medial cuneiform. This structure was statically inserted between the navicular and medial cuneiform, which would allow the pull of the tibialis posterior to act on the navicular and medial cuneiform in tandem. The average width of the naviculocuneiform ligament was 15.2 mm (range 12.4-18.0) compared to 9.5 mm (range 7.6-11.4) for the tibialis posterior tendon. CONCLUSION:: The tibialis posterior tendon inserted into the navicular and continued onto the medial cuneiform to provide a static restraint between 2 bony insertions, thus supporting the distal aspect of the medial longitudinal arch. CLINICAL RELEVANCE:: We are confident that it is a structure of importance in maintaining the distal aspect of the medial longitudinal arch and may therefore have significant clinical and surgical implications when treating the pes planus deformity.

How Do I Use the Scarf Osteotomy to Rotate the Metatarsal and Correct the Deformity in Three Dimensions?

The scarf osteotomy has become the workhorse procedure for a large proportion of foot and ankle surgeons, especially in Europe, in the treatment of hallux valgus. Such a versatile procedure should not be underestimated, and planning and thought should precede any such procedure. The angle of bone cuts and magnitude of translation dictate the final position, and all movement axes should be given equal attention.