Surgical Reconstruction of Type IV Hypoplasia of the Thumb (Floating Thumb) in Infants: A Retrospective Analysis of Functional Outcomes and Radiographic Alignment.

BACKGROUND Congenital hypoplasia of the thumb type IV, also known as floating thumb, is a condition in which 2 small phalanges are attached to the hand with a thin skin bridge. Surgical management options for this condition vary from amputation to flap reconstruction. MATERIAL AND METHODS This retrospective study analyzed 11 infants with congenital hypoplasia of the thumb type IV who underwent surgical reconstruction using a modified vascularized polydactylous hallux flap. The study included 6 male and 5 female infants, aged 6 to 24 months. Functional evaluations and radiographic studies were conducted postoperatively. RESULTS All 11 patients underwent the complete surgical protocol. Successful vascular and nerve anastomoses were performed during the initial procedure, ensuring sufficient blood supply and neural connectivity to the transferred toes. The second operation showed promising outcomes, including improvements in thumb opposition, grasp strength, and overall function. Postoperative assessments demonstrated satisfactory radiographic alignment and no major complications during the follow-up period. CONCLUSIONS The modified vascularized polydactylous hallux flap reconstruction is a viable surgical option for managing congenital hypoplasia of the thumb type IV in infants. This technique effectively restores thumb opposition, grasp strength, and overall hand function, with satisfactory radiographic alignment and minimal complications. The study findings support the efficacy and safety of this surgical approach in addressing this rare congenital anomaly.

Kinematic Investigation of Healthy, Arthritic, and Postsurgery Thumbs: Is the Metacarpophalangeal Joint the Gateway to Carpometacarpal Arthritis?

The thumb carpometacarpal (CMC) joint is one of the most likely joints to develop osteoarthritis (OA). If conservative treatments fail to alleviate symptoms, surgery may be pursued. Kinematic outcomes of CMC surgery techniques have been described, but current tools have limitations in capturing motion abilities. The goals of this study were (1) develop a new and robust set of kinematic outcome measures, and apply them to (2) a cohort of younger and older control individuals without CMC OA to determine age and sex-related changes, and (3) a cohort of participants with CMC OA before, 3 months, and 6 months after undergoing thumb ligament reconstruction with tendon interposition surgery to detect the impacts of surgery. 52 (26 males, 26 females) control and 18 (3 males, 15 females) surgical participants were tested. Kinematics were investigated using motion capture by mapping the three-dimensional motion space of the whole thumb, and two-dimensional motion boundaries of the metacarpal (MC) and proximal phalange (PP). Visual analog pain score was recorded. Older control participants had shifted regions of motion compared to younger participants (p ≤ 0.027), suggesting asymptomatic CMC wear. Control females had 31% more metacarpophalangeal (MCP) motion than control males (p = 0.013), which could alter loading paths through the CMC joint and increase OA risk. Pain at 6 months postsurgery was 72% less than presurgery (p < 0.001), but motion abilities were 20-28% less than presurgery (p ≤ 0.074) and 24-40% less than control participants (p ≤ 0.066). These techniques have the possibility of identifying presymptomatic motion changes, including those at the metacarpophalangeal joint in CMC OA progression.

The Female Thumb Carpometacarpal Joint: Motion and Force Changes Due to Arthritis and Surgical Intervention.

Thumb carpometacarpal (CMC) osteoarthritis (OA) has been one of the most common locations of hand OA. CMC OA disproportionately occurs in females over males. In severe cases, surgical intervention may be needed. However, to determine the effects of surgical treatment, normative, pre-, and postsurgery function must be understood. The goals of this work were to compare the thumb motion and force abilities of older healthy (OH) females without CMC OA to those of females with CMC OA and who received ligament reconstruction with tendon interposition (LRTI) surgery at time points presurgery, 3- and 6-months postsurgery. On average, CMC OA participants 3- and 6-months postsurgery showed 35.6% and 32.9% less overall metacarpal motion compared to presurgery, 31.9% and 29.1% less than OH, and exhibited altered motion. Metacarpal flexion/extension and abduction/adduction ranges were 51.9 deg and 43.4 deg for OH, 52.9 deg and 40.3 deg presurgery, 39.9 deg and 33.5 deg at 3-months, and 42.6 deg and 32.7 deg at 6-months postsurgery. On average, participants had increased force generation at 6-months postsurgery compared to presurgery, and 20% of participants returned to the level of OH females. These data sets highlight changes in thumb metacarpal movement and thumb force generation due to disease and surgical intervention. This work has the ability to support both surgeons and patients through improved outcome assessments as well as additional data to inform the decision process on intervention.

Arthrodesis of distal interphalangeal and thumb interphalangeal joint: a retrospective cohort study of 149 cases.

BACKGROUND: Arthrodesis of finger joints is often the last line of treatment of severe pain due to osteoarthritis, rheumatoid arthritis, or mallet finger. At the Department of Orthopedic and Hand Surgery, Örebro University Hospital (ÖUH) in Sweden, the Kirschner-wire technique was standard until 2020, when the headless compression screw technique was introduced as a complement. There is no consensus on which method is superior. The purpose of this study was to examine the outcomes and complications associated with distal interphalangeal (DIP) joint and thumb interphalangeal (IP) joint arthrodesis, and to see whether these correlated with patient-dependent and treatment-related factors. METHODS: In a retrospective cohort study, we evaluated a total of 149 consecutive arthrodeses (118 DIP joint and 31 thumb IP joint) performed between 2012 and 2022. The primary outcome was risk factors for complications after arthrodesis. RESULTS: Osteoarthritis was the most common indication (56%) for arthrodesis. The majority of the patients were females (74%), and the median age was 62 (range 18-86). The complication frequency was 35%, with infection being the most common (25%). Time to completed follow up was < 12 weeks in the majority of the cases (58%). There were no significant differences in complication rate between the 136 joints operated using Kirschner wire and the 13 joints operated using headless compression screws. There was no significant increased risk of complications among smokers or patients with rheumatoid arthritis. Diabetes and surgeon experience had a significant influence on the risk of complication (p = 0.036 and p = 0.006, respectively). CONCLUSIONS: Osteoarthritis was the most common indication for arthrodesis and postoperative complications occurred at a rate similar to that reported in the existing literature. Diabetes and surgeon experience were identified as factors increasing the risk of postoperative complications in these DIP/thumb IP joint arthrodeses. However, there was no significant difference between the two techniques (Kirschner wire and headless compression screws) regarding complications. Further studies are needed in order to determine the optimal type of operation and choice of implant. TRIAL REGISTRATION: Researchweb CRIS #280,998, 26th of July 2023.

Mid- and long-term clinical results of the Elektra and Moovis prosthesis for trapeziometacarpal joint replacement.

BACKGROUND: Total joint arthroplasty as a surgical treatment option for trapeziometacarpal joint arthritis is recently revived. The aim of this study is to report on mid- and long-term results of the Elektra (single-mobility) and Moovis (dual-mobility) prosthesis for treatment of primary thumb carpometacarpal joint arthritis. METHODS: In this retrospective, monocentric, descriptive cohort study, 31 prostheses were evaluated that were implanted by a single surgeon in 26 patients between 2009 and 2019. Indication for surgery was trapeziometacarpal joint osteoarthritis (Eaton/Littler Stage II and III). Clinical and radiological follow-up was performed at a minimum of 24 months. The postoperative assessment included range of motion, pain, strength as well as functional scores (DASH, MHQ). Implant survival and complications were the primary endpoints. RESULTS: 10 Elektra and 21 Moovis prostheses were implanted between 2009 and 2019 with a mean follow-up of 74.2 months in the Elektra and 41.4 months in the Moovis group. The average patients' age at surgery was 64 years. Postoperative pain levels (VAS 0-10) were below 2 at rest and under stress in both groups. Grip/pinch strength and range of motion showed results comparable to the contralateral hand. Opposition was excellent with an average Kapandji index of 9.6 in both groups. Elektra achieved slightly better functional scores in the DASH and MHQ score. Satisfaction was high in both groups, and 96% of the patients would recommend the procedure. Metacarpophalangeal hyperextension > 15° was seen in 3 patients per group preoperatively and was corrected to < 5° post-surgery. 3 Elektra prostheses were revised due to cup loosening and dislocation for cup and/or neck replacement or secondary trapeziectomy. 1 Moovis prosthesis was revised with an exchange of the neck to a larger size due to restricted movement. After the mean follow-up of 7.9 years in Elektra and 3.5 years in MOOVIS, cumulative survival was 68.6% vs. 95.2%, respectively. CONCLUSIONS: In this mid- to long-term retrospective analysis, total joint arthroplasty in primary trapeziometacarpal joint arthritis results in low pain levels, excellent mobility and clinical function. Patient satisfaction is overall high. While revision due to cup loosening occurred more often in patients with single-mobility implants, no cases of dislocation or loosening of components were observed in the dual-mobility group. TRIAL REGISTRATION: The study was conducted in accordance with the Declaration of Helsinki, and approved by the Ethics Committee of the Medical Faculty of Heidelberg University, reference number S-150/2020.

High Fracture Rate of AVANTA Silicone Implant Following Arthroplasty of the Thumb MCP Joint of Rheumatoid Arthritis Patients with Boutonniere Deformities.

We retrospectively investigated the mid-term outcomes of arthroplasty using the AVANTA silicone implant for thumb metacarpophalangeal (MCP) joints with boutonniere deformity in patients with rheumatoid arthritis (RA). This study involved 36 thumbs of 33 RA patients with a mean follow-up period of 5.1 years (range, 2.0-13.3). Postoperatively, the mean extension was significantly increased and the mean flexion was significantly decreased (p<0.001, p<0.001, respectively), resulting in the mean arc of range of motion (ROM) shifting in the direction of extension after surgery. Implant fracture was observed in 10 thumbs (28%), and 4 of these (11%) underwent revision surgery. The survivorship with implant fracture and revision surgery as endpoints were 73.4% and 91.8% at 5 years, respectively. The preoperative arc of ROM and the postoperative flexion range of the implant-fracture group were significantly greater than those in the no-implant-fracture group (p=0.039, 0.034, respectively). These results suggest the importance of patient education and careful rehabilitation to prevent excessive flexion. Overall, the AVANTA silicone implant showed a relatively high rate of implant fracture at our institute.

Conjoined Free Fibula Transplantation and First Carpometacarpal Joint Prosthesis for Functional Thumb Reconstruction-A Case Report.

BACKGROUND: Giant cell tumors grow locally invasive with osseous and soft tissue destruction, requiring wide resection to avoid recurrence. Stable reconstruction of the first carpometacarpal (CMC-1) joint remains a challenge due to its high range of mobility. The latter is of paramount for the functionality of the hand. PURPOSE: Therefore, the aim of this study was to report our approach for a combined reconstruction of the first metacarpal and the CMC-1 joint. METHODS: A 58-year-old woman underwent wide resection of a benign giant cell tumor at the base and shaft of the first metacarpal of the left thumb. Because of the loss of the CMC-1 joint and the instability of the thumb, an osseous reconstruction using a vascularized fibular graft combined with a TOUCH Dual Mobility CMC-1 prosthesis was performed to reconstruct the CMC-1 joint. RESULTS: Osseous healing was observed after 3 months. No tumor recurrence and good joint function were documented at the follow-up investigation after 1 year. The patient reported only minor restrictions during activities of daily living. Thumb opposition was possible with a Kapandji score of 8/10. A slight pain while walking remained as a donor-side morbidity at the right lower leg. CONCLUSION: Metacarpal reconstruction with vascularized fibula bone grafts allowed a combined joint reconstruction with a commercially available prosthesis, which is an approach to restore the complex range of motion of the thumb.

U-shaped kirschner wire transfixation: effective treatment for Skier's thumb.

BACKGROUND: Skier's thumb is a type of injury to the ulnar collateral ligament of the metacarpophalangeal joint of the thumb, which can result in bone fragmentation and joint instability. OBJECTIVE: The objective of this study was to compare the traditional Kirschner wire fixation method with the U-shaped Kirschner wire method for treating small bone fragments with displacement, rotation, or instability in skier's fractures. METHOD: A retrospective study was conducted on 30 patients with skier's thumb who were treated at Tianjin Hospital from January 2019 to December 2021. Patients were divided into two groups: Group A received traditional Kirschner wire fixation, while Group B received U-shaped Kirschner wire fixation. Functional assessments and complications during the perioperative period were evaluated. RESULTS: Both surgical methods significantly reduced postoperative pain and increased joint range of motion. Group B had a lower incidence of pain during follow-up and showed significant functional improvement in Tip-pinch and Grip tests compared to Group A. U-shaped Kirschner wire fixation significantly reduced complications during the perioperative period. CONCLUSION: The U-shaped Kirschner wire internal fixation is a safe and effective treatment for the thumb proximal phalanx base ulnar side avulsion fracture.

Predicting Contralateral Surgery for Trapeziometacarpal Arthrosis Within 5 Years.

PURPOSE: Symptomatic trapeziometacarpal (TMC) joint arthritis is a common cause of hand pain. It is unknown how many patients ultimately elect to have bilateral surgery for TMC arthritis. In this study, we assessed the frequency and predictive factors for contralateral TMC surgery in patients who underwent prior TMC surgery. METHODS: We identified 712 patients who underwent primary surgery for TMC arthritis with a follow-up period of 5 years. We collected demographic, surgical, and follow-up data. Prediction models for contralateral surgery using a training and testing data set were created with multivariable logistic regression and random forest classifier algorithms. RESULTS: At the time of initial surgery, 230 patients had bilateral thumb pain (32%), but only 153 patients ultimately had an operation for TMC arthritis on the contralateral side within 5 years (21% of 712 total patients and 67% of 230 patients with bilateral pain). Common predictive factors between both models for contralateral surgery were younger age (odds ratio [OR] = 0.95; 95% confidence interval [CI], 0.93-0.98), bilateral thumb pain (OR = 3.76; 95% CI, 2.52-5.65), and anxiety disorders (OR = 1.84; 95% CI, 1.11-3.03). CONCLUSIONS: In our study, we found that the rate of contralateral surgery was 21% in patients who underwent prior TMC surgery. Predictive factors for future contralateral surgery included younger age, bilateral thumb pain, and anxiety disorder at the time of initial surgery. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.

Biological Versus Nonbiological Reconstruction of the Ulnar Collateral Ligament of the Thumb Metacarpophalangeal Joint: A Retrospective Study.

PURPOSE: The purpose of this study was to compare clinical and radiologic outcomes of biological ligament reconstruction (BLR) versus nonbiological ligament reconstruction (NBLR) for chronic injuries involving the ulnar collateral ligament of the thumb's metacarpophalangeal joint. METHODS: Forty-two patients who underwent static BLR (n = 24) or NBLR (n = 18) were included in this retrospective analysis. Preoperative, postoperative, and contralateral thumb measurements (clinical evaluation, radiographs, and subjective outcome questionnaires) were compared over a mean of 38 months of follow-up. RESULTS: Average postoperative thumb metacarpophalangeal and interphalangeal joint ranges of motion were 2° to 54° and 0 to 71°, respectively, for BLR and 0° to 58° and 0° to 71°, respectively, for NBLR. Average grip and pinch strengths, relative to the unaffected hand, were 102% and 84% versus 103% and 89%, respectively. All patients demonstrated stability with a firm end point, compared with the unaffected thumb. The average Quick Disabilities of the Arm, Shoulder, and Hand score among all patients was 12 for the disability/symptom module, 0 for the sports module, and 17 for the work module. Stiffness was reported among four patients, and no patient sustained wound-related issues or other complications. CONCLUSIONS: Nonbiological ligament reconstruction of the thumb ulnar collateral ligament generates short-term outcomes comparable with those of BLR, potentially allowing for expedited recovery and rehabilitation. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Small Joint Denervation of the Hand and Thumb Base: History, Anatomy, Technique, and Outcomes.

Painful arthritis of the small joints of the hand is a common condition affecting older adults, with distal interphalangeal joint and thumb carpometacarpal joint being the two most common locations. Younger adults may also develop painful arthritis after trauma and with inflammatory arthropathy. Traditional surgical approaches address the structure of the joints with either arthrodesis or arthroplasty with or without an implant. In recent decades, denervation has been reported as an alternative treatment for painful small joints that are mobile and stable. Publications on denervation often report faster surgery and recovery times than traditional surgeries that manipulate the small joint bony structures. This article reviews the history, anatomy, surgical techniques, and outcomes of denervation of the small joints of the hand.

Application of extended ulnar parametacarpal perforator free flap for the reconstruction of total pulp defect of the thumb: A case report.

Many procedures are available for the coverage of thumb pulp defects; however, to gain thumb function and esthetics, a similar tissue is desirable. If the length of the longitudinal defect is <2 cm, a volar advancement flap is appropriate; however, if the flap is >2 cm long or wider, retrograde or free flaps are required. Here, we present a case of thumb pulp reconstruction using an extended ulnar parametacarpal perforator (UPM) flap, which achieved excellent functional and esthetic outcomes. A 46-year-old man underwent reconstruction surgery of his thumb, which was a degloved total pulp. A sensate 5.2 × 3.2 cm UPM flap was designed on the ulnar side of the right palm and transferred to his thumb. The flap donor site was covered with a V-Y advancement flap on the dorsal side of the right hand. At 12 months postoperatively, the patient achieved a functional and natural thumb appearance with high satisfaction. The UPM flap can offer soft tissue similar to the pulp region in the digit without a palm scar at the donor site. This extended application is suitable for the reconstruction of a total pulp defect of the digit and is an alternative option for a hemi-pulp flap from the toe area.

Minimally invasive arthroscopy-assisted arthrodesis for thumb carpometacarpal osteoarthritis.

INTRODUCTION: Arthrodesis is a reliable surgical procedure for treatment of thumb carpometacarpal (CMC) osteoarthritis that provides hand strength and pain relief. Locking plate fixation is a common technique that provides rigid fixation and a high rate of bone union; however, it requires extensive surgical exploration of the first metacarpal and trapezium. Here, we report the surgical outcome of minimally invasive arthroscopy-assisted thumb CMC arthrodesis that preserves soft tissue supplying the blood flow to the bones. MATERIALS AND METHODS: Nine thumbs of nine patients who underwent arthroscopy-assisted thumb CMC arthrodesis were retrospectively analysed (mean postoperative follow-up, 19.7 months). We investigated the time from surgery to bone union, grip strength, pinch strength (pulp and key), range of motion (ROM) of the thumb, visual analogue scale (VAS) score for pain, Disabilities of Arm, Shoulder, and Hand (DASH) score, and Hand20 questionnaire score preoperatively and at the final follow-up. RESULTS: Bone union was observed in eight of the nine patients. The mean time to bone union was 2.9 months (range 8 weeks-9 months). Although grip strength changed from 24.0 kg preoperatively to 25.8 kg at the final follow-up (not significant), the pulp pinch strength and key pinch strength significantly increased from 2.3 kg and 3.7 kg preoperatively to 3.8 kg and 5.6 kg at the final follow-up, respectively. No significant change occurred in the thumb ROM. The DASH score, Hand20 questionnaire score, and VAS score for pain significantly improved from 29.8, 42.2, and 78.4 preoperatively to 12.4, 11.2, and 13.2 at the final follow-up, respectively. Non-union was observed in one patient. No other complications were observed. CONCLUSIONS: Arthroscopy-assisted arthrodesis is a valuable procedure for thumb CMC osteoarthritis. However, the learning curve for this procedure must be overcome before the operative time can be shortened and successful bone union and satisfactory outcomes achieved.

Basal osteotomy of the first metacarpal using patient-specific guides and instrumentation: biomechanical and 3D CT-based analysis.

INTRODUCTION: The aim of this study was to investigate the radiological outcomes of proximal closing metacarpal extension osteotomies using patient-specific guides and instruments (PSI) in early-stage trapeziometacarpal osteoarthritis to gain further insight into the joint loading surface and the benefits of the procedure. METHODS: In a prospective observational study, nine patients were included between 11/2020 and 12/2021, undergoing a total of ten proximal metacarpal extension osteotomies for basal thumb osteoarthritis. Computer-assisted surgical planning was performed using computed tomography (CT) and three-dimensional (3D) segmentation, allowing the fabrication of 3D-printed PSIs for surgical treatment. Inclusion criteria were a 1-year follow-up by CT to assess postoperative correction of the positional shift of the first metacarpal (MC1) and the location of peak loads compared with the preoperative situation. RESULTS: Radiographic analysis of the peak loading zone revealed a mean displacement on the articular surface of the trapezius of 0.4 mm ± 1.4 mm to radial and 0.1 mm ± 1.2 mm to palmar, and on the articular surface of the MC1 of 0.4 mm ± 1.4 mm to radial and 0.1 mm ± 1.2 mm to dorsal. CONCLUSION: There were trends indicating that a flatter pressure distribution and a dorsal shift of the peak loading zone may contribute to an improvement in subjective pain and patient satisfaction associated with this surgical procedure. The non-significant radiological results and the minor dorsal-radial shifts in our small study group limit a firm conclusion. LEVEL OF EVIDENCE: III.

Total joint arthroplasty for thumb carpometacarpal joint osteoarthritis: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND AND PURPOSE: Thumb carpometacarpal (CMC) joint osteoarthritis (OA) is increasingly treated with total joint arthroplasty (TJA). We aimed to perform a systematic review and meta-analysis of the benefits and harms of the TJA for thumb CMC OA compared with other treatment strategies. PATIENTS AND METHODS: We performed a systematic search on MEDLINE and CENTRAL databases on August 2, 2023. We included randomized controlled trials investigating the effect of TJA in people with thumb CMC joint OA regardless of the stage or etiology of the disease or comparator. The outcomes were pooled with a random effect meta-analysis. RESULTS: We identified 4 studies randomizing 420 participants to TJA or trapeziectomy. At 3 months, TJA's benefits for pain may exceed the clinically important difference. However, after 1-year follow-up TJA does not improve pain compared with trapeziectomy (mean difference 0.53 points on a 0 to 10 scale; 95% confidence interval [CI] 0.26-0.81). Furthermore, it provides a transient benefit in hand function at 3 months (measured with Disabilities of Arm, Shoulder, and Hand questionnaire, scale 0-100, lower is better) compared with trapeziectomy with or without ligament reconstruction tendon interposition. The benefit in function diminished to a clinically unimportant level at 1-year follow-up (4.4 points better; CI 0.42-8.4). CONCLUSION: Transient benefit in hand function for TJA implies that it could be a preferable option over trapeziectomy for people who consider fast postoperative recovery important. However, current evidence fails to inform us if TJA carries long-term higher risks of revisions compared with trapeziectomy.

Patient-Experience of Trapeziectomy for Trapeziometacarpal Osteoarthritis in Wide-Awake Local Anesthesia no Tourniquet, 2-Year Follow-up.

PURPOSE OF THE STUDY: The purpose of this study was to assess the patient experience of trapeziectomy under WALANT for trapeziometacarpal joint (TMJ) osteoarthritis (OA) in a prospective study with 2-year follow-up. MATERIAL AND METHODS: The study included 23 patients with TMJ OA undergoing trapeziectomy with WALANT. All patients were seen by a hand therapist preoperatively and at 3, 12, and 24 months postoperatively. At each visit, VAS pain scores, thumb range of motion, grip strength, and Disabilities of the Arm, Shoulder and Hand (DASH) score were assessed. The Picker Patient Experience (PPE-15) questionnaire was administered within 2 weeks of surgery. RESULTS: All 23 patients completed the PPE-15 questionnaire. Their mean age was 64 years. The 21 patients who remained at the 24-month follow-up all said they would choose the same anaesthesia method again. At this follow-up, VAS pain scores, thumb range of motion, key pinch grip and DASH scores had improved significantly, while thumb opposition and hand grip strength remained largely unchanged. The majority of patients felt well informed before and during the procedure, and all patients rated pain relief as good or satisfactory. Nearly 40% of patients reported receiving inadequate information about the postoperative medications. DISCUSSION: Patients have a positive attitude to trapeziectomy with WALANT, and seem to prefer WALANT over other methods of anaesthesia. Trapeziectomy with WALANT for TMJ OA is a safe procedure and appears to give a functional outcome similar to trapeziectomy under general anaesthesia. CONCLUSIONS: Trapeziectomy with WALANT for TMJ OA is safe, preferred by patients and has similar clinical outcome as trapeziectomy in general anesthesia. KEY WORDS: trapeziectomy, osteoarthritis, WALANT.

A review of wear debris in thumb base joint implants.

AIM: Polymers and metals, such as polyethylene (PE) and cobalt chrome (CoCr), are common materials used in thumb-based joint implants, also known as CMC (Carpometacarpal) arthroplasty. The purpose of this review was to investigate the reported failure modes related to wear debris from these type of materials in CMC implants. The impact of wear debris on clinical outcomes of CMC implants was also examined. Potential adverse wear conditions and inflammatory particle characteristics were also considered. METHOD: A literature search was performed using PRISMA guidelines and 55 studies were reviewed including 49 cohort studies and 6 case studies. Of the 55 studies, 38/55 (69%) focused on metal-on-polyethylene devices, followed by metal-on-metal (35%), and metal-on-bone (4%). RESULTS: The summarized data was used to determine the frequency of failure modes potentially related to wear debris from metals and/or polymers. The most commonly reported incidents potentially relating to debris were implant loosening (7.1%), osteolysis (1.2%) and metallosis (0.6%). Interestingly the reported mechanisms behind osteolysis and loosening greatly varied. Inflammatory reactions, while rare, were generally attributed to metallic debris from metal-on-metal devices. Mechanisms of adverse wear conditions included implant malpositioning, over-tensioning, high loading for active patients, third-body debris, and polyethylene wear-through. No specific examination of debris particle characterization was found, pointing to a gap in the literature. CONCLUSION: This review underscores the types of failure modes associated with wear debris in CMC implants. It was found that failure rates and adverse wear conditions of CMC implants of any design are low and the exact relationship between wear debris and implant incidences, such as osteolysis and loosening remains uncertain. The authors note that further research and specific characterization is required to understand the relationship between debris and implant failure.

Dorsal Subluxation of the First Metacarpal During Thumb Flexion is an Indicator of Carpometacarpal Osteoarthritis Progression.

BACKGROUND: Measurable changes in patients with progression of thumb carpometacarpal (CMC) osteoarthritis (OA) include joint space narrowing, osteophyte formation, subluxation, and adjacent-tissue changes. Subluxation, an indication of mechanical instability, is postulated as an early biomechanical indicator of progressing CMC OA. Various radiographic views and hand postures have been proposed to best assess CMC subluxation, but 3D measurements derived from CT images serve as the optimal metric. However, we do not know which thumb pose yields subluxation that most indicates OA progression. QUESTIONS/PURPOSES: Using osteophyte volume as a quantitative measure of OA progression, we asked: (1) Does dorsal subluxation vary by thumb pose, time, and disease severity in patients with thumb CMC OA? (2) In which thumb pose(s) does dorsal subluxation most differentiate patients with stable CMC OA from those with progressing CMC OA? (3) In those poses, what values of dorsal subluxation indicate a high likelihood of CMC OA progression? METHODS: Between 2011 and 2014, 743 patients were seen at our institutions for trapeziometacarpal pain. We considered individuals who were between the ages of 45 and 75 years, had tenderness to palpation or a positive grind test result, and had modified Eaton Stage 0 or 1 radiographic thumb CMC OA as potentially eligible for enrollment. Based on these criteria, 109 patients were eligible. Of the eligible patients, 19 were excluded because of a lack of interest in study participation, and another four were lost before the minimum study follow-up or had incomplete datasets, leaving 86 (43 female patients with a mean age of 53 ± 6 years and 43 male patients with a mean age of 60 ± 7 years) patients for analysis. Twenty-five asymptomatic participants (controls) aged 45 to 75 years were also prospectively recruited to participate in this study. Inclusion criteria for controls included an absence of thumb pain and no evidence of CMC OA during clinical examination. Of the 25 recruited controls, three were lost to follow-up, leaving 22 for analysis (13 female patients with a mean age of 55 ± 7 years and nine male patients with a mean age of 58 ± 9 years). Over the 6-year study period, CT images were acquired of patients and controls in 11 thumb poses: neutral, adduction, abduction, flexion, extension, grasp, jar, pinch, grasp loaded, jar loaded, and pinch loaded. CT images were acquired at enrollment (Year 0) and Years 1.5, 3, 4.5, and 6 for patients and at Years 0 and 6 for controls. From the CT images, bone models of the first metacarpal (MC1) and trapezium were segmented, and coordinate systems were calculated from their CMC articular surfaces. The volar-dorsal location of the MC1 relative to the trapezium was computed and normalized for bone size. Patients were categorized into stable OA and progressing OA subgroups based on trapezial osteophyte volume. MC1 volar-dorsal location was analyzed by thumb pose, time, and disease severity using linear mixed-effects models. Data are reported as the mean and 95% confidence interval. Differences in volar-dorsal location at enrollment and rate of migration during the study were analyzed for each thumb pose by group (control, stable OA, and progressing OA). A receiver operating characteristic curve analysis of MC1 location was used to identify thumb poses that differentiated patients whose OA was stable from those whose OA was progressing. The Youden J statistic was used to determine optimized cutoff values of subluxation from those poses to be tested as indicators of OA progression. Sensitivity, specificity, negative predictive values, and positive predictive values were calculated to assess the performance of pose-specific cutoff values of MC1 locations as indicators of progressing OA. RESULTS: In flexion, the MC1 locations were volar to the joint center in patients with stable OA (mean -6.2% [95% CI -8.8% to -3.6%]) and controls (mean -6.1% [95% CI -8.9% to -3.2%]), while patients with progressing OA exhibited dorsal subluxation (mean 5.0% [95% CI 1.3% to 8.6%]; p < 0.001). The pose associated with the most rapid MC1 dorsal subluxation in the progressing OA group was thumb flexion (mean 3.2% [95% CI 2.5% to 3.9%] increase per year). In contrast, the MC1 migrated dorsally much slower in the stable OA group (p < 0.001), at only a mean of 0.1% (95% CI -0.4% to 0.6%) per year. A cutoff value of 1.5% for the volar MC1 position during flexion at enrollment (C-statistic: 0.70) was a moderate indicator of OA progression, with a high positive predictive value (0.80) but low negative predictive value (0.54). Positive and negative predictive values of subluxation rate in flexion (2.1% per year) were high (0.81 and 0.81, respectively). The metric that most indicated a high likelihood of OA progression (sensitivity 0.96, negative predictive value 0.89) was a dual cutoff that combined the subluxation rate in flexion (2.1% per year) with that of loaded pinch (1.2% per year). CONCLUSION: In the thumb flexion pose, only the progressing OA group exhibited MC1 dorsal subluxation. The MC1 location cutoff value for progression in flexion was 1.5% volar to the trapezium , which suggests that dorsal subluxation of any amount in this pose indicates a high likelihood of thumb CMC OA progression. However, volar MC1 location in flexion alone was not sufficient to rule out progression. The availability of longitudinal data improved our ability to identify patients whose disease will likely remain stable. In patients whose MC1 location during flexion changed < 2.1% per year and whose MC1 location during pinch loading changed < 1.2% per year, the confidence that their disease would remain stable throughout the 6-year study period was very high. These cutoff rates were a lower limit, and any patients whose dorsal subluxation advanced faster than 2% to 1% per year in their respective hand poses, were highly likely to experience progressive disease. CLINICAL RELEVANCE: Our findings suggest that in patients with early signs of CMC OA, nonoperative interventions aimed to reduce further dorsal subluxation or operative treatments that spare the trapezium and limit subluxation may be effective. It remains to be determined whether our subluxation metrics can be rigorously computed from more widely available technologies, such as plain radiography or ultrasound.

Congenital hypoplastic thumbs treated by staged nonvascularized MTP joint transfer for absent MCP joints and abductor digiti minimi tendon transfer for opposition: a case series study.

BACKGROUND: We developed a 2-stage, MTP (metatarsophalangeal) joint- plus ADM (abductor digiti minimi) tendon-transfer, procedure for treatment of hypoplastic thumb. This method is intended to achieve both structural and functional goals of reconstruction. Structurally, it preserves a five-digit hand with minimal donor site complications. Functionally, it provides a functioning opposable thumb. CASE PRESENTATION: The case series included 7 patients with type IV hypoplastic thumb. At the first stage non-vascularized joint (not bone) was transplanted. In the second stage abductor digiti minimi tendon was transferred. Patients were followed for a median 5-yr period (range: 37-79 months). Functional outcome was assessed using a modified Percival assessment tool. Participants aged 17 to 36 months at the time of surgery with (2 male, 4 female). All patients were able to grasp large and small objects after the procedure. The thumb tip could actively move to touch the tips of index (2 patients) middle, ring, and little fingers (all patients) in an ulnar ward sequence and vice versa. All patients attained the ability to do lateral, palmar, and tripod pinch. As for donor site complications, none of the patients were found to have difficulty walking or keeping their balance. CONCLUSIONS: An alternative surgical procedure was developed to reconstruct a hypoplastic thumb. We obtained a good functional and cosmetic outcome with few donor site complications. Future studies will be needed to determine the long-term outcomes, to refine the selection criteria and to examine the necessity of additional procedure at the older ages.

Arthrodesis of the interphalangeal joints of the hand by two-dimensional intraosseous wiring.

BACKGROUND: Numerous techniques for arthrodesis have been described to fix interphalangeal (IP) joints, and the fixation method should be considered on a case-by-case basis. This study aimed to investigate the availability of IP joint arthrodesis of the hand, using a two-dimensional intraosseous wiring (two-DIOW) method. METHODS: A total of 43 joints (19 thumb IP joints, 9 proximal finger interphalangeal (PIP) joints and 15 distal interphalangeal (DIP) joints in 29 patients with a mean age of 66 years (range, 24-85 y) were retrospectively analyzed. All operations were performed with two-DIOW method. We evaluated the bone union rate, correction loss, presence of any surgical complications, and oral steroid use in cases of joint fixation using the two-DIOW method. RESULTS: Of these 43 digits, 42 achieved bone union (97.7%). Non-union was seen in a thumb IP joint of mutilans rheumatoid arthritis. Mean correction loss of deviation was 1.0°, and flexion or extension angulation was 1.6° in the direction of extension. Surgical complications included mild nail deformity in 2 digits and wire irritation necessitating wire removal in 2 digits. Oral steroids were used for 18 of the 43 digits, including 2 digits complicated by nail deformities. There was no infection and skin necrosis in all digits with or without steroid use. CONCLUSIONS: The two-DIOW method appears to offer an effective method of IP joint fixation, but caution should be exercised in digits of severe joint destruction and in the treatment of wire knot.