Mid-term outcomes of 77 modular radial head prostheses

AIMS: Radial head arthroplasty (RHA) may be used in the treatment of non-reconstructable radial head fractures. The aim of this study was to evaluate the mid-term clinical and radiographic results of RHA. PATIENTS AND METHODS: Between 2002 and 2014, 77 RHAs were implanted in 54 men and 23 women with either acute injuries (54) or with traumatic sequelae (23) of a fracture of the radial head. Four designs of RHA were used, including the Guepar (Small Bone Innovations (SBi)/Stryker; 36), Evolutive (Aston Medical; 24), rHead RECON (SBi/Stryker; ten) or rHead STANDARD (SBi/Stryker; 7) prostheses. The mean follow-up was 74.0 months (standard deviation (sd) 38.6; 24 to 141). The indication for further surgery, range of movement, mean Mayo Elbow Performance (MEP) score, quick Disabilities of the Arm, Shoulder and Hand (quickDASH) score, osteolysis and positioning of the implant were also assessed according to the design, and acute or delayed use. RESULTS: The mean MEP and quickDASH scores were 90.2 (sd 14; 45 to 100), and 14.0 points (sd 12; 1.2 to 52.5), respectively. There were no significant differences between RHA performed in acute or delayed fashion. There were 30 re-operations (19 with, and 11 without removal of the implant) during the first three post-operative years. Painful loosening was the primary indication for removal in 14 patients. Short-stemmed prostheses (16 mm to 22 mm in length) were also associated with an increased risk of painful loosening (odds ratio 3.54 (1.02 to 12.2), p = 0.045). Radiocapitellar instability was the primary indication for re-operation with retention of the implant (5). The overall survival of the RHA, free from re-operation, was 60.8% (sd 5.7%) at ten years. CONCLUSION: Bipolar and press-fit RHA gives unsatisfactory mid-term outcomes in the treatment of acute fractures of the radial head or their sequelae. The outcome may vary according to the design of the implant. The rate of re-operation during the first three years is predictive of the long-term survival in tight-fitting RHAs

Tight-fitting radial head prosthesis: does stem size help prevent painful loosening?

INTRODUCTION: The most common reason for removal of well-fixed radial head prostheses is painful loosening. We hypothesised that short-stemmed prostheses, used for radial head arthroplasty, are not associated with an increased risk of implant loosening. METHODS: From 2002 to 2014, 65 patients were enrolled in a retrospective single-centre study. The radial head prostheses were classified as having either a long (30-mm) or short (16- to 22-mm) stem. The long-stemmed implants comprised 30 GUEPAR® DePuy Synthes (West Chester, PA, USA) and 20 Evolutive® Aston Medical (Saint-Etienne, France) devices; the short-stemmed implants comprised nine RECON and six STANDARD rHead® SBI-Stryker (Morrisville, PA, USA) devices. At last follow-up, clinical (range of motion, Disabilities of the Arm, Shoulder, and Hand score, Mayo Elbow Performance score) and radiographic (osteolysis) outcomes were assessed. RESULTS: At a mean follow-up of 76.78 months (24-141), the rate of painful loosening [6 (40%) vs 8 (16%), p = 0.047] and osteolysis [12 (80%) vs 23 (46%), p = 0.02] were significantly higher in patients with short-stemmed versus long-stemmed implants. Despite the significant difference in loosening between stems as groups, individual stem length was not determined. CONCLUSIONS: Tight-fitting implants with short stems are more prone to painful loosening

Radial head arthroplasty: a historical perspective

There has been lively debate regarding the rationale behind the use of radial head arthroplasty (RHA) for more than 80 years. Currently, its primary indication is for treatment of non-reconstructible RH fractures. The first RH implant, released in 1941, was a ferrul cap used to prevent heterotopic ossification. Biomechanical studies in the 1980s stimulated a revolution in RHA design by promoting modular implants that replicated the native bony anatomy of the elbow. Subsequent data-driven evolution in design led to the creation of a variety of devices that also accommodated for common ligamentous injuries occurring at the time of RH fracture. Despite significant advances in our understanding of complex elbow instability, improvements in implant design have to make RHA the gold standard for treatment of non-reconstructible RH fractures. The challenge in the coming years will be to perform high-level clinical studies in order to obtain consensus regarding the most appropriate treatment for comminuted RH fractures

The minimum follow-up required for radial head arthroplasty

AIMS: The primary aim of this study was to define the standard minimum follow-up required to produce a reliable estimate of the rate of re-operation after radial head arthroplasty (RHA). The secondary objective was to define the leading reasons for re-operation. MATERIALS AND METHODS: Four electronic databases, between January 2000 and March 2017 were searched. Articles reporting reasons for re-operation (Group I) and results (Group II) after RHA were included. In Group I, a meta-analysis was performed to obtain the standard minimum follow-up, the mean time to re-operation and the reason for failure. In Group II, the minimum follow-up for each study was compared with the standard minimum follow-up. RESULTS: A total of 40 studies were analysed: three were Group I and included 80 implants and 37 were Group II and included 1192 implants. In Group I, the mean time to re-operation was 1.37 years (0 to 11.25), the standard minimum follow-up was 3.25 years; painful loosening was the main indication for re-operation. In Group II, 33 Group II articles (89.2%) reported a minimum follow-up of < 3.25 years. CONCLUSION: The literature does not provide a reliable estimate of the rate of re-operation after RHA. The reproducibility of results would be improved by using a minimum follow-up of three years combined with a consensus of the definition of the reasons for failure after RHA

Degenerative subtalar joints complicated by medial plantar intraneural cysts

AIMS: The pathogenesis of intraneural ganglion cysts is controversial. Recent reports in the literature described medial plantar intraneural ganglion cysts (mIGC) with articular branches to subtalar joints. The aim of the current study was to provide further support for the principles underlying the articular theory, and to explain the successes and failures of treatment of mICGs. PATIENTS AND METHODS: Between 2006 and 2017, five patients with five mICGs were retrospectively reviewed. There were five men with a mean age of 50.2 years (33 to 68) and a mean follow-up of 3.8 years (0.8 to 6). Case history, physical examination, imaging, and intraoperative findings were reviewed. The outcomes of interest were ultrasound and/or MRI features of mICG, as well as the clinical outcomes. RESULTS: The five intraneural cysts followed the principles of the unifying articular theory. Connection to the posterior subtalar joint (pSTJ) was identified or suspected in four patients. Re-evaluation of preoperative MRI demonstrated a degenerative pSTJ and denervation changes in the abductor hallucis in all patients. Cyst excision with resection of the articular branch (four), cyst incision and drainage (one), and percutaneous aspiration/steroid injection (two) were performed. Removing the connection to the pSTJ prevented recurrence of mIGC, whereas medial plantar nerves remained cystic and symptomatic when resection of the communicating articular branch was not performed. CONCLUSION: Our findings support a standardized treatment algorithm for mIGC in the presence of degenerative disease at the pSTJ. By understanding the pathoanatomic mechanism for every cyst, we can improve treatment that must address the articular branch to avoid the recurrence of intraneural ganglion cysts, as well as the degenerative pSTJ to avoid extraneural cyst formation or recurrence

Short to midterm outcomes of one hundred and seventy one MoPyC radial head prostheses: meta-analysis

The MoPyC implant is an uncemented long-stemmed radial head prosthesis that obtains primary press-fit fixation via controlled expansion of the stem. Current literature regarding MoPyC implants appears promising; however, sample sizes in these studies are small. Our primary objective was to evaluate the short- to midterm clinical outcomes of a large sample of the MoPyC prostheses. The secondary objective was to determine the reasons for failure of the MoPyC devices. METHODS: Four electronic databases were queried for literature published between January 2000 and March 2017. Articles describing clinical and radiographic outcomes as well as reasons for reoperation were included. A meta-analysis was performed to obtain range of motion, mean Mayo Elbow Performance score (MEPS), radiographic outcome, and reason for failure. RESULTS: A total of five articles describing 171 patients (82 males) with MoPyC implants were included. Mean patient age and follow-up were 52 years (18-79) and 3.1 years (1-9), respectively. Midterm clinical results were good or excellent (MEPS > 74) in 157 patients. Overall complication rate was low (n = 22), while periprosthetic osteolysis was reported in 78 patients. Nineteen patients returned to the operating room, with implant revision being required in ten patients. The two primary reasons for failure were (intra-)prosthetic dislocation (n = 8) followed by stiffness (n = 7); no painful loosening was described. CONCLUSION: Short- to midterm outcomes of MoPyC prostheses are satisfactory and complications associated are low. The use of stem auto-expansion as a mode of obtaining primary fixation in radial head arthroplasty appears to be an effective solution for reducing the risk of painful loosening

Causes for early and late surgical re-intervention after radial head arthroplasty

PURPOSE: The primary objective was to describe the reasons for surgical re-intervention after radial head arthroplasty. The secondary objective was to analyze the radiographic and clinical outcomes after surgical re-intervention at the elbow with implant conservation. METHODS: Among the 70 radial head arthroplasties with bipolar radial head implant performed between 2002 and 2014, 29 required surgical re-interventions. Reasons for surgical re-intervention were gathered from operative notes and follow-up documentation. Patients who underwent re-intervention with implant retention were reassessed via clinical and radiographic examinations by an independent reviewer. RESULTS: Twenty nine re-operations were performed at a mean follow-up of 16 ± 11.7 months (0.2-36 months). The prosthesis was removed in 18 cases and retained in 11. There was a significant difference in mean time to re-intervention between the implant removal and preservation groups, 23.1 ± 8.3 months (7-36 months) and 4.4 ± 4.7 months (0.2-13 months), respectively (p < 0.001). The primary reason for surgical re-intervention was painful loosening (13 cases). Radio-capitellar instability was the most frequent reason for re-intervention with implant retention (5 cases). Midterm quickDASH and MEPS after surgical re-intervention with implant retention were 15.4 ± 5.4 and 82.27 ± 7.3, respectively. At least one degenerative lesion was reported in nine cases (81.8%) (i.e. 5 periprosthetic osteolysis, 5 capitellar wear, 5 periarticular heterotopic ossification). CONCLUSIONS: Painful loosening and capitellar instability are the primary reasons for surgical re-intervention with or without implant removal. Midterm clinical results are favourable despite an elevated rate of degenerative lesions after surgical re-intervention with implant retention

Ultrasonography study of the suprascapular nerve

PURPOSE: The aim of the study was to evaluate the assessability of the suprascapular nerve (SSN) by ultrasonography in cadavers and healthy volunteers. MATERIALS AND METHODS: With ultrasonography guidance, needles were placed at origin of the SSN of four cadavers and evaluated by dissection. Two blinded radiologists performed 60 ultrasonography scans in 30 healthy volunteers to study the entire SSN at five anatomical landmarks. RESULTS: Dissection revealed that the needles were correctly located at the nerve's origin. There were no significant differences between the two radiologists' measurements of nerve size and depth. The interobserver correlation for the description of the nerve at the five predefined anatomical landmarks was very good (ICC=0.7-1). CONCLUSION: Five anatomical landmarks were used to analyze the SSN with ultrasonography. Its supraclavicular portion was easier to describe than its scapular portion; a segment of the SSN was not visible between these two portions

Delayed reconstruction and high BMI z score increase the risk of meniscal tear in paediatric and adolescent anterior cruciate ligament injury

PURPOSE: The purpose of this study was to identify epidemiologic risk factors for secondary meniscal tears in paediatric and adolescent patients who sustain an anterior cruciate ligament (ACL) tear. The hypothesis was that delayed reconstruction and elevated BMI z score, increase the risk for secondary meniscal tears. METHODS: A prospective, descriptive and analytical study of consecutively accrued children and adolescents with an ACL tear was performed. One hundred and sixty subjects (114 males and 46 females) were identified between 2006 and 2015 at one institution. The age range was between 7 and 19 years. Fifteen parameters were recorded and analysed: age at initial trauma, initial trauma circumstance, sex, BMI z score, affected side, type of sport, Tegner score, athletic level, time to MRI, time to first referral, time to surgery, age at surgery, attempted non-operative treatment, operative report and associated meniscal tear. These meniscal lesions could be diagnosed by an MRI and / or during surgery. RESULTS: Out of the 160 cases, 143 were treated surgically and 17 cases non-operatively. Median corrected BMI z score was 0.5 (range - 1.8 to 4.7). 41.9% had one or more meniscal lesions. 55 patients were initially treated non-operatively, of which 39 patients were secondarily operated. There was a positive relationship between meniscal lesion and: BMI z score (p = 0.0364), attempted non-operative treatment (p = 0.001) and time to surgery (p = 0.002). The median time to ACL reconstruction was 229 days for patients with secondary meniscal lesions. CONCLUSIONS: Patients with ACL tears treated non-operatively developed secondary meniscal lesions requiring delayed surgical management. There was a positive correlation between BMI z score and secondary meniscal lesions. Thus, early ACL reconstruction is advocated in young athletes

Does a combined screw and dowel construct improve tibial fixation during anterior cruciate ligament reconstruction?

Purpose: The aims of the present study were to compare the biomechanical properties of tibial fixation in hamstring-graft ACL reconstruction using interference screw and a novel combination interference screw and dowel construct. Material and methods: We compared the fixation of 30 (2- and 4-stranded gracilis and semitendinosis tendons) in 15 fresh-frozen porcine tibiae with a biocomposite resorbable interference screw (Group 1) and a screw and dowel construct (Group 2). Each graft was subjected to load-to-failure testing (50 mm/min) to determine maximum load, displacement at failure and pullout strength. Results: There were no significant differences between the biomechanical properties of the constructs. Multivariate analysis demonstrated that combination constructs (β = 140.20, p = 0.043), screw diameter (β = 185, p = 0.006) and 4-strand grafts (β = 51, p = 0.050) were associated with a significant increase in load at failure. Larger screw diameter was associated with increased construct stiffness (β = 20.15, p = 0.020). Conclusion: The screw and dowel construct led to significantly increased fixation properties compared to interference screws alone in a porcine model. Increased screw diameter and utilization of 4-strand ACL grafts also led to improvement in load-to-failure of the construct. However, this is an in vitro study and additional investigations are needed to determine whether the results are reproducible in vivo. Level of evidence: Level V; Biomechanical study