Abstract. Aim. This study aims to Inter and intra observer reliability compare, use of a standard goniometer (SG) to measure intermetacarpal angle (degrees) vs use of a new technique of using a digital vernier calliper (DVC) (mm) to measure the distance between the first and second metacarpal head. Method. Maximal active abduction and extension of both thumbs was measured in 20 healthy volunteers on two occasions at least one week apart by two assessors. Results. The inter and intra-observer agreement was higher & the variance of the data was lower using the DVC with the new technique than the SG for both thumb abduction and extension. Additionally, the correlation between measurement of extension and abduction was higher using the DVC than the SG. Conclusion. Whilst both tools provide acceptable intra and inter-observer agreement, the new technique using a DVC is consistently better and more reliable than a SG in measuring thumb abduction and extension. The study also supports our hypothesis that the thumb rotates around the second metacarpal head with a consistent radius

Introduction. Despite the rising popularity of 1st carpometacarpal joint (CMCJ) arthrodesis as one of the surgical options for basilar thumb arthritis, the available literature on this is poor. This study aims to investigate post-operative pinch and grip strength following 1st CMCJ arthrodesis, at a minimum of 1 year follow-up. Complication rates, range of motion and patient reported scores were also evaluated. Methods. A retrospective cohort (2012–2020) was used, which included patients who had arthrodesis performed by the Hands surgeons at Counties Manukau DHB. In a 15 minute visit, we took the measurements using our standard dynamometer and pinch gauge, and collected three questionnaires [QuickDASH, PRWHE, PEM]. For analysis, we compared our results to the preoperative measures, contralateral hand, and to a previous study on a similar cohort looking at thumb strength following trapeziectomy. Results. 42 arthrodesis were performed, and 24 were available for follow-up. The average follow-up time was 77 months and the average age was 51 years old. Overall, we found a statistically significant improvement in thumb strength following surgery. Mean preoperative grip strength was 21.4kg and 32.5kg postoperatively (= +11kg). Preoperative pinch strength was 5.5kg and 7kg postoperatively (= +1.5kg). These results were significantly higher compared to the trapeziectomy cohort. We also found an improvement in 1st CMCJ ROM post-operatively. 7 complications were reported (29.1%). 4 were metalware-related and 3 were non-union. QuickDASH score significantly improved from a median of 42.95 to 12.5 while PRWHE from 67.5 to 14.5. Overall patient satisfaction was 87.4%. Conclusion. 1st CMCJ arthrodesis leads to an improvement in thumb function, pain and range of movement and results in high patient satisfaction, and therefore should be recommended for younger patients who need a pain-free and strong thumb

Trapeziectomy with ligament reconstruction and tendon interposition (LRTI) with the flexor carpi radialis (FCR) tendon is one of the most common procedures for the treatment of thumb carpometacarpal (CMC) arthritis. An alternative method involves trapeziectomy alone (TA). The trapeziectomy with LRTI procedure was developed to theoretically improve biomechanical strength and hand function when compared to TA, which leaves an anatomical void proximal to the first metacarpal. The LRTI procedure takes longer to perform and includes an autologous tendon graft. The goal of this retrospective cohort study was to evaluate the clinical outcomes of trapeziectomy with or without LRTI at a minimum follow-up of 1 year. A total of 43 adult patients who had underwent a total of 58 (TA=36, LRTI=22) surgical procedures for CMC arthritis participated in the study. This single surgeon retrospective cohort study sampled patients who underwent CMC arthroplasty with either TA or LRTI techniques between 2008 and 2020 with a minimum time of 1 year post-operatively. The patients were evaluated subjectively (The Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire) and objectively (hand/thumb strength, pre/post-operative hand radiographs). Both the TA and LRTI procedures provided good pain relief, motion, strength, and stability without any severe complications. There was no statistically significant difference in hand or thumb strength between the two groups. Radiography showed that compared to the preoperative status, the trapezial space decreased similarly between the two groups. There was no difference in size of collapse between TA and LRTI post-operatively. The TA procedure had similar outcomes to LRTI and has the advantages of shorter surgical time, less incision length, and lower surgical complexity. TA provided equivalent trapezial space to LRTI after the operation. Future study should investigate these two procedures in a head-to-head comparison rather than longitudinally where both surgeon experience and time since procedure at follow-up may have impacted results

Introduction. An understanding of anatomic variability can help guide the surgeon on intervention strategies. Well-functioning thumb metacarpophalangeal joints (MCPJ) are essential for carrying out typical daily activities. However, current options for arthroplasty are limited. This is further hindered by the lack of a precise understanding of the geometric variation present in the population. In this paper, we offer new insight into the major modes of geometric variation in the thumb MCP using Statistical Shape Modelling. Methods. Ten participants free from hand or wrist disease or injury were recruited for CT imaging (Ethics Ref:14/LO/1059). 1. Participants were sex matched with mean age 31yrs (range 27–37yrs). Metacarpal (MC1) and proximal phalanx (PP1) bone surfaces were identified in the CT volumes using a greyscale threshold, and meshed. The ten MC1 and ten PP1 segmented bones were aligned by estimating their principal axes using Principal Component Analysis (PCA), and registration was performed to enable statistical comparison of the position of each mesh vertex. PCA was then used again, to reduce the dimensionality of the data by identifying the main ‘modes’ of independent size and shape variation (principal components, PCs) present in the population. Once the PCs were identified, the variation described by each PC was explored by inspecting the shape change at two standard deviations either side of the mean bone shape. Results. For the ten MC1s, over 80% of the variation was described by the first two PCs (Table 1). Figure 1 shows the effect of the variation in PC1. The majority of geometric variation of the ten PP1s was also described by the first two PCs, with PC1 describing 78.9%. Figure 2 shows the effect of this component on the mean bone geometry. Both the distal articulating surface (head) of the MC1 and the proximal articulating surface (base) of the PP1 vary in overall size. However, the MC1 head also varies in shape (curvature), whereas the PP1 base does not appear to undergo noticeable variation in shape. In this study population, smaller MC1 was observed to correlate with a flatter head, whereas the PP1 head shape did not vary with size. Discussion. The flatter MC1 head (smaller height-radius ratio) may have implications for MCPJ instability, and possibly for osteoarthritic degeneration. A recent study predicted similar trends for the first CMC joint. 2. Previous investigation also observed correlation between MC1 head curvature and MCPJ RoM. 3. , which may explain clinical observations of differing thumb movement strategies. This study used a convenience sample and cannot describe a full population's variability, though the high variance captured by only two PCs suggests adequate external validity amongst similar populations. Further confidence would be gained from studying the joint (i.e. single PCA containing both bones), and wider populations. Significance. These data: provide more precise description of anatomic variation; may offer insights into thumb movement strategies and MCPJ osteoarthritic degeneration. 4. ; and support implant design for individuals whose anatomy can bear an anatomic reconstruction. For any figures or tables, please contact the authors directly

There is no agreement as to the superiority or specific indications for cast treatment, percutaneous pinning or open fracture fixation for Bennett's fractures of the thumb metacarpal. We undertook this study to compare the outcomes of treatment for patients treated for Bennett's fracture in the medium term. We reviewed 33 patients treated in our unit for a bennett's fracture to the thumb metacarpal with closed reduction and casting. Each patient was matched with a patient treated surgically. Patients were matched for sex, age, Gedda grade of injury and hand dominance. Patients were reviewed at a minimum of 5-years and 66-patients were reviewed in total. Patients were examined clinically and also asked to complete a DASH questionnaire score and the brief Michigan hand questionnaire. Follow up plain radiographs were taken of the thumb and these were reviewed and graded for degenerative change using the Eaton-Littler score. Sixty-six patients were included in the study, with 33 in the surgical and non-surgical cohorts respectively. The average age was 39 years old. In each cohort, 12/33 were female, 19/33 were right-handed with 25% of individuals injuring their dominant hand. In each coort there were 16 Grade 1 fractures, 4 Grade 2 and 13 Grade 3 fractures. There was no difference between the surgically treated and cast-treatment cohorts of patients when radiographic arthritis, pinch grip, the brief Michigan Hand Questionnaire and pain were assessed at final review. The surgical cohort had significantly lower DASH scores at final follow-up. There was no significant difference in the normalised bMHQ scores. Our study was unable to demonstrate superiority of either operative or non-operative fracture stabilization. Patients in the surgical cohort reported superior satisfaction and DASH scores but did not demonstrate any superiority in any other objectively measured domain

Thumb Carpometacarpal (CMC) arthritis is a common pathology of the hand. Surgical treatment with thumb reconstruction is well described. Retrospective outcomes have been described for multiple techniques, suggesting patient satisfaction with multiple different techniques. The Thompson technique uses a slip of Abductor Pollicis Longus for suspension and interposition as well as excision of the trapezium. Retrospective outcomes suggest good patient satisfaction. We describe the improvement in Patient rated outcomes scores (PROS) and changes in pinch and grip strength in a prospectively collected cohort of patients treated with a modification of the Thompson technique. To assess changes in Patient-Rated Wrist Evaluation (PRWE) and Disabilities of the Arm, Shoulder, and Hand (QDASH) scores, as well as to determine the percentage of patients that surpassed the Minimal Clinically Important Difference (MCID) figure that has been described in the literature for these tests. In addition, measurements for evaluation of pinch and grip strength prior to surgery, at six, and at twelve months follow-up were done. Between June 2016 and February 2019, a consecutive prospective series of Thirty-seven LRTI procedures with APL suspension arthroplasty (Thompson technique) were performed on 34 patients with osteoarthritis of the thumb CMC joint (24 women / 13 men; age 63±8.553). All surgeries were performed by the senior surgeon. Data was collected as part of a wrist pain database. Patients failing conservative treatment and electing surgical management of thumb arthritis were enrolled into the database. Patients were evaluated pre-operatively with the PRWE and QDASH questionnaires and grip and pinch strength measurements, and postoperatively at 6 and 12 months. The MCID for QDASH and PRWE is 14 and will be evaluated at the same time points for each patient. Paired student T-test was used to determine differences in the means. Data are presented as mean ± SD unless stated otherwise. Differences with p<.05 were considered significant. Compared to the pre-operative assessment, at six months, the means of PRWE pain score and PRWE functional score decreased significantly (32.824 SD±10.721 vs. 19.265 SD±12.268 and 30.262 SD±10.050 vs. 16.431 SD± 9.697 respectively, n=34,, p<0.05). 69% of the patients surpassed the MCID of 14 six months after the surgery. In addition, QDASH mean score also dropped from 56.108 to 32.219 (SD± 21.375 n=32. p<0.05) at six months. At one year, 76% of the patients were above the MCID of 14. The mean scores of these three questionnaires did not show significant change between six and twelve months. Compared to the initial pre-operative assessment, we found no statistically significant difference in the means of grip strength, point pinch, and lateral key pinch at six and twelve months. Thumb reconstruction with APL suspension arthroplasty demonstrates significant improvement in pain and functionality. No significant improvement in grip and pinch strength is observed, even at one year postoperatively

There is no consensus for the appropriate surgical management of chronic ulnar collateral ligament (UCL) injuries of the thumb. A systematic review of Pubmed, MEDLINE, EMBASE and ePub Ahead of Print was performed in accordance with Preferred Reporting of Items in Systematic Review and Meta-analysis (PRISMA) guidelines and formal protocol registered with PROSPERO. Two authors collated data from 10 studies that met strict inclusion criteria, using various surgical techniques in 131 thumbs. Results were heterogenous and metanalysis of results not possible. These data were, therefore, qualitatively assessed and synthesised. Bias was assessed using the ROBINS-I tool. Direct repair, reconstruction with free tendon or bone-tissue-bone grafts and arthrodesis all demonstrated favourable outcomes with Patient Reported Outcome Measures. Direct repair can be safely performed more than two months following injury, with a positive mean Disabilities of the Arm, Shoulder and Hand (DASH) score of 13.5 despite evidence of radiographic osteoarthritis. Arthrodesis should be considered in heavy manual laborers or those at risk of osteoarthritis as it provides significant reduction in pain (Mean Visual Analogue Score of 1.2) when compared to other methods. Free tendon grafting has been criticised for failure rates and poor functional grip strength, however collated analysis of 97 patients found a single graft rupture and mean grip strength of 97% (of the contralateral thumb). Bone-tissue-bone grafting was the least effective method across all outcome measures. Studies included were at high risk of bias, however, it can be concluded that delayed direct repair can be performed safely, while arthrodesis may benefit certain patient subgroups. New findings suggest poor efficacy of bone-tissue-bone grafts, but that free tendon grafting with palmaris longus are in fact safe with good restoration of grip strength. The optimal graft and configuration are yet to be determined for reconstructive methods

The opposable thumb is one of the defining characteristics of human anatomy and is involved in most activities of daily life. Lack of optimal thumb motion results in pain, weakness, and decrease in quality of life. First carpometacarpal (CMC1) osteoarthritis (OA) is one of the most common sites of OA. Current clinical diagnosis and monitoring of CMC1 OA disease are primarily aided by X-ray radiography; however, many studies have reported discrepancies between radiographic evidence of CMC1 OA and patient-related outcomes of pain and disability. Radiographs lack soft-tissue contrast and are insufficient for the detection of early characteristics of OA such as synovitis, which play a key role in CMC OA disease progression. Magnetic resonance imaging (MRI) and two-dimensional ultrasound (2D-US) are alternative options that are excellent for imaging soft tissue pathology. However, MRI has high operating costs and long wait-times, while 2D-US is highly operator dependent and provides 2D images of 3D anatomical structures. Three-dimensional ultrasound imaging may be an option to address the clinical need for a rapid and safe point of care imaging device. The purpose of this research project is to validate the use of mechanically translated 3D-US in CMC OA patients to assess the measurement capabilities of the device in a clinically diverse population in comparison to MRI. Four CMC1-OA patients were scanned using the 3D-US device, which was attached to a Canon Aplio i700 US machine with a 14L5 linear transducer with a 10MHz operating frequency and 58mm. Complimentary MR images were acquired using a 3.0 T MRI system and LT 3D coronal photon dense cube fat suppression sequence was used. The volume of the synovium was segmented from both 3D-US and MR images by two raters and the measured volumes were compared to find volume percent differences. Paired sample t-test were used to determine any statistically significant differences between the volumetric measurements observed by the raters and in the measurements found using MRI vs. 3D-US. Interclass Correlation Coefficients were used to determine inter- and intra-rater reliability. The mean volume percent difference observed between the two raters for the 3D-US and MRI acquired synovial volumes was 1.77% and 4.76%, respectively. The smallest percent difference in volume found between raters was 0.91% and was from an MR image. A paired sample t-test demonstrated that there was no significant difference between the volumetric values observed between MRI and 3D-US. ICC values of 0.99 and 0.98 for 3D-US and MRI respectively, indicate that there was excellent inter-rater reliability between the two raters. A novel application of a 3D-US acquisition device was evaluated using a CMC OA patient population to determine its clinical feasibility and measurement capabilities in comparison to MRI. As this device is compatible with any commercially available ultrasound machine, it increases its accessibility and ease of use, while proving a method for overcoming some of the limitations associated with radiography, MRI, and 2DUS. 3DUS has the potential to provide clinicians with a tool to quantitatively measure and monitor OA progression at the patient's bedside

Background. We would like to analyze the risk factors of no thumb test among knee alignment tests during total knee arthroplasty surgery. Methods. The 156 cases of total knee arthroplasty by an operator from October 2009 to April 2010 were analyzed according to preoperative indicators including body weight, height, degree of varus deformity, and patella subluxation and surgical indicators such as pre-osteotomy patella thickness, degree of patella degeneration, no thumb test which was evaluated after medial prepatella incision and before bone resection (1st test), no thumb test which was evaluated with corrective valgus stress (2nd test, J test), and the kind of prosthesis. We comparatively analyzed indicators affecting no thumb test (3rd test). Results. There was no relation between age, sex, and body weight and no thumb test (3rd test). Patellar sulcus angle (p = 0.795), patellar congruence angle (p = 0.276) and preoperative mechanical axis showed no relationship. The 1st no thumb test (p = 0.007) and 2nd test (p = 0.002) showed signifi cant relation with the 3rd no thumb test. Among surgical indicators, pre-osteotomy patella thickness (p = 0.275) and degeneration of patella (p = 0.320) were not relevant but post-osteotomy patellar thickness (p = 0.002) was relevant to no thumb test (3rd test). According to prosthesis, there was no signifi cance with Nexgen (p = 0.575). However, there was signifi cant correlation between Scorpio (p = 0.011), Vanguard (p = 0.049) and no thumb test (3rd test). Especially, Scorpio had a tendency to dislocate the patella, but Vanguard to stabilize the patella. Conclusions. No thumb test (3rd test) is correlated positively with 1st test, 2nd test, and post-osteotomy patella thickness. Therefore, the more patella osteotomy and the prosthesis with high affi nity to patellofemoral alignment would be required for correct patella alignment

Introduction. There are conflicting reports about the efficacy of injection to the thumb carpometacarpal joint (CMCJ) for osteoarthritis (OA). The accuracy of joint injection without radiological control is unclear. We investigated the accuracy of blind injection and recorded their immediate and short term efficacy. Materials/Methods. We injected 25 consecutive patients between March 2010-January 2011. The CMCJ was palpated, manually distracted and a 23 gauze needle introduced blindly. Image intensifier was then used to visualize and redirect needle if necessary. Radio-opaque dye was injected to confirm intra-articular placement. We recorded patient demographics, number of attempts required for correct needle placement, pre and 10 minutes post-injection visual analogue scale (VAS) pain score, and Nelson Score (NS)before and six weeks after injection. NS is a validated thumb CMCJ specific patient administered questionnaire. Results. Mean age was 60 (range 46–90). M:F ratio was 23:2. CMC J OA ranged from grade 2–4.1. st. attempt was successful in 6 cases. Mean attempts required for accurate injection was 3 (range 0–4). Mean pain pre- injection VAS was 7 (range 4–10), 10 minutes following injection 0.5 (range 0–4) and at 6 weeks 5 (range 3–10). Mean pre-operative NS was 29.6 (range 14–65) and at 6 weeks 32.4 (range 14–55). The difference was not statistically significant (paired t test, p=0.24). Conclusion. Our results suggest that blind injection of thumb CMCJ may not be accurate. Accuracy can be improved by X-ray guided injection. The procedure afforded excellent immediate pain relief but was not effective over six weeks follow up

Thumb carpometacarpal (CMC) arthritis is a common and disabling condition that can be treated with an operative procedure. Before operative measures, patients typically undergo conservative treatment utilizing methods such as physical therapy and injections. This study aims to determine what clinical modalities are being used for preoperative evaluation and nonoperative therapy and the associated cost prior to operative intervention. We queried Truven Market Scan, a large insurance provider database to identify patients undergoing CMC arthroplasty from 2010 to 2017. Patients were identified by common Current Procedural Terminology (CPT) codes for CMC arthroplasty. All associated CPT codes listed for each patient during the 1 year period prior to operative intervention were collected and filtered to only include those codes associated with the ICD-9/10 diagnosis codes relating to CMC arthritis. The codes were then categorized as office visits, x-ray, injections, physical therapy, medical devices, and preoperative labs. The frequency and associated cost for each category was determined. There were 44,676 patients who underwent CMC arthroplasty during the study period. A total of $26,319,848.36 was charged during the preoperative period, for an average of $589.13 per patient. The highest contributing category to overall cost was office visits (42.1%), followed by injections (13.5%), and then physical therapy (11.1%). The most common diagnostic modality was x-ray, which was performed in 74.7% of patients and made up 11.0% of total charges. Only 49% of patients received at least one injection during the preoperative period and the average number of injections per patient was 1.72. Patients who were employed full time were more likely to receive two or more injections prior to surgery compared to patients who had retired (47% of full-time workers; 34% of retirees). The modalities used for the preoperative evaluation and conservative treatment of CMC arthritis and the associated cost are important to understand in order to determine the most successful and cost-effective treatment plan for patients. Surprisingly, despite the established evidence supporting clinical benefits, many patients do not undergo corticosteroid injections. With office visits being the largest contributor to overall costs, further inquiry into the necessity of multiple visits and efforts to combine visits, can help to reduce cost. Also, with the advent of telemedicine it may be possible to reduce visit cost by utilizing virtual medicine. Determining the best use of telemedicine and its effectiveness are areas for future investigation

The carpometacarpal joint of the thumb is one of the most common locations of degenerative arthritis. Surgical options include trapezio-metacarpal fusion, replacement or resection arthroplasty with or without interposition. We report the medium term results of a Modified Thompson's suspensionplasty. The radial half of the APL tendon was looped around the FCR tendon to create the suspension. The remainder of the tendon is then used for interposition. We carried out a retrospective review of 50 patients (67 hands) who underwent this procedure from January 1999 to December 2005. There were 41 female (52 hands) and 9 male (15 hands). The average age at the time of surgery was 62 years (range 41 years – 79 years). The average follow up was 5.33 years (1-9 yrs). 22 patients also had a concurrent second procedure to the same thumb and a further three had a third procedure. The average PRWHE score was 25 (0 – 80) and the average DASH score was 40 (24 – 100). There were eight complications which included four persistent radial sided wrist pain. Two of these underwent tenotomy of FCR, whilst two responded to conservative measures. Two patients had symptoms related to scapho-trapezoid arthritis, which responded to an injection. One patient had superficial infection which settled with oral antibiotics, whilst another patient had early chronic regional pain syndrome. Overall the satisfaction rate was 90% with 48 patients (96%) willing to undergo the same procedure again. We conclude that the modified Thompson's suspensionplasty gives excellent medium term results

Background. The current treatment options available for Trapezio-metacarpal arthritis are injection, splint and ultimately surgery. The injections are predominantly done by General practitioners and no data is available to specialist. Aim. To investigate accuracy of injection and efficacy of injection in terms of short and long term pain relief. Methods. We recruited 25 patients during March 2010 - January 2011. All of these patients had AP, Lat, and special Roberts radiographs. The technique involved palpating and surface marking Trapezio-metacarpal joint in the theatre. Under fluoroscopy, needle placement was performed while the operator was blinded from the screen. The location of needle was confirmed and then operator was allowed visualize the position of needle. Every movement of needle or the thumb to get the needle in joint was considered as an attempt. All had premixed Local anaesthetic and Depomedrone injection in to the joint. Accuracy was confirmed by operator and patient. We recorded patient demographics, number of attempts required for correct needle placement, pre and 10 minutes post-injection visual analogue scale (VAS) pain score, and Nelson Score (NS)before and six weeks after injection. Results. Mean age was 60(range 46–90). M:F(23:2). Dominant hand was affected in 14 cases. CMC J OA ranged from grade 2–4. First attempt was successful in 6 cases. Mean attempts required for accurate injection was 3(range 0–4). Mean pain pre-injection VAS was 7(range 4–10), 10 minutes following injection 0.5(range 0–4) and at 6 weeks 5(range 3–10). Mean pre-operative NS was 29.6(range 14–65) and at 6 weeks 32.4(range 14–55). The difference was not statistically significant (paired t test, p=0.24). Conclusion. Our results suggest that blind injection of thumb CMCJ may not be accurate as it requires assessment and appreciation of surface anatomy. Accuracy can be definitely improved by radiological guided injection. Limitations. Small number and short follow up

Thumb carpometacarpal joint (CMCJ) arthritis is a common and debilitating condition. The mainstay of surgical management is Trapeziectomy. Concerns about possible functional implications of collapse of the metacarpal into the arthroplasty space as well as the potential for scaphometacarpal led to the development of techniques to try and prevent this. The purpose of this study was to investigate if there were any significant differences in the long-term outcomes of patients who participated in a randomized trial of trapeziectomy alone compared with trapeziectomy with ligament reconstruction and tendon interposition (LRTI). Sixty-five patients participated in our original trial, the 1 year findings of which were published in 2007. These patients were invited for a follow-up visit at a mean of 17 years (range 15–20) postoperatively. Twenty-eight patients attended, who had 34 operations, 14 trapeziectomy alone and 20 with LRTI. Patients were asked to complete a visual analogue scale (VAS) for satisfaction with the outcome of their procedure, rated on a scale from 0 (most dissatisfied) to 100 (most satisfied). They also completed the short version of the Disabilities of the Arm, Shoulder and Hand Score (QuickDASH) at their appointment. They underwent a functional assessment with a hand therapist and had a radiograph of the thumb. There were no statistically significant differences between the two groups in terms of satisfaction with surgery or functional outcomes, with most measurements showing minimal or no differences in means between the two groups. There was no difference in the space between the metacarpal and scaphoid on radiograph. Radial abduction was the only parameter that was significantly greater in the patients with simple trapeziectomy (median 79°) compared with trapeziectomy with LRTI (median 71°) (p = 0.04). Even at 17 years there is no significant benefit of LRTI over trapeziectomy alone for thumb carpometacarpal joint osteoarthritis

Introduction. The trapezio-metacarpal joint (TMCJ) is subject to constant multiplanar forces and is stabilised by the bony anatomy and ligamentous structures. Ligament reconstruction can correct the hypermobility and potentially prevent osteoarthritis. Eaton and Littler proposed a surgical technique to reconstruct the volar ligamentous support of this joint. In our cadaveric biomechanical study, we aimed to evaluate the resultant effect of this technique on the mobility of the thumb metacarpal. Materials and method. Seventeen cadaveric hands were prepared and placed on a custom-made jig. Movements at the trapeziometacarpal joint were created using weights. Static digital photographs were taken with intact anterior oblique (AOL) and ulnar collateral ligaments(UCL) and compared with those taken after sectioning these ligaments and following Eaton-Littler reconstructive technique. The photographic records were analyzed using Scion. Image™. Paired T-test was used to establish statistical significance with a p<0.05. Results. AOL and UCL stabilised the TMCJ in extension. Division of these ligaments produced a significant degree of subluxation of the metacarpal at this joint with the thumb in a neutral position. Reconstruction of the ligamentous supports, using the Eaton-Littler technique, reduced the degree of extension. Conclusion. The primary stabilising ligament of the TMCJ is a subject of debate. Our study objectively evaluates the effect of reconstruction of AOL and UCL on various movements at the TMCJ comparing with sectioned and unsectioned specimens. It confirms the role AOL and UCL in resisting extension and utility of the Eaton-Littler procedure in decreasing hyperextension at this joint. This may have clinical utility in traumatic injury and degenerative laxity, by reducing pain and potentially slowing or even preventing the progression of osteoarthritis

The Mathys. ¯. finger joint replacement system offers a novel fixation method into the proximal and distal medullary canals and a semi-constrained articulation. This comprises a separable, form-fit joint with a distal/proximal play of 0.7 mm, a lateral excursion of 10°, and rotation of up to 6°. This has theoretical advantages of increased radio-ulnar stability, preventing ulnar drift in patients with rheumatoid disease, and enhanced osseointegration offering implant longevity. In our unit, however, high failure rates were noted, prompting a review of cases to quantify our suspicions. Case notes of all patients who underwent finger joint replacement using the Mathys. ¯. implant between 1999 and 2005 were retrieved. Twenty-two devices were implanted by a single surgeon during this period. Four were in finger proximal interphalangeal joints, 17 in finger metacarpophalangeal joints and one in a thumb carpometacarpal joint (CMCJ). Indications for joint replacement included sixteen for rheumatoid arthritis (RA) and five for post-traumatic joint problems. The only thumb CMCJ was replaced for primary osteoarthritis. Patients were reviewed regularly and implant performance assessed critically along with survival of the implant to revision, infection or death of the patient. Mean follow up was 30 months. Sixteen implants failed including the only thumb CMCJ. Modes of failure were rotation (11), poor range of motion (two), infection (two) and dislocation (the CMCJ). Similar ball and socket designs for uncemented thumb CMCJ replacement, such as the Ledoux prosthesis, have previously shown poor survival and have been withdrawn from the market. Of the finger implants in RA patients (n=16), 12 implants failed of which ten were due to rotation. Time to failure ranged from two to 48 months (mean 15 months). The authors do not recommend the use of this implant, especially in cases of rheumatoid arthritis

Background. A randomised prospective study has already demonstrated that at 1-year follow-up, palmaris longus interposition or flexor carpi radialis (FCR) ligament reconstruction and tendon interposition do not improve the outcome of trapeziectomy for the treatment of painful osteoarthritis of the trapeziometacarpal joint. This study consisted of 183 thumbs in 162 women. Aims. 114 of the 183 thumbs have now completed their 5-year follow-up and this study reports their results. Patients and methods. The patients had been prospectively randomised for treatment by simple trapeziectomy without interposition or ligament reconstruction (T; n=45), trapeziectomy with palmaris longus interposition (T+PL; n=31) or ligament reconstruction and tendon interposition (T+LRTI; n=38) using 50% of the FCR tendon. Each patient had undergone assessments of thumb pain, stiffness and strength pre-operatively, at 3 months, at 1 year and after a minimum of 5 years post-operatively. Results. The three treatment groups were well matched for age and hand dominance. At the 5 year follow-up, 76% (T=80%; T+PL=71%; T+LRTI=76%) of the 114 patients had no pain or only mild pain after use. Thumb key pinch strengths at the 5 year follow-up did not differ significantly between the three procedures [T= 4.0 kg (95%CI, 3.6-4.4); T+PL= 3.6 kg (95%CI, 2.9-4.3); T+LRTI= 3.6 kg (95%CI, 3.1-4.1)]. The tip pinch strengths at 5 years were also similar after each of the operations [T= 2.7 kg (95%CI, 2.4-2.9); T+PL= 2.4 kg (95%CI, 1.9-2.9); T+LTRI= 2.5 kg (95%CI, 2.1-2.9)]. No cases of late deterioration were evident at 5 years. Conclusion. The outcomes of these three variations of trapeziectomy appear identical. Thus at 5 years, there appears to be no benefit to tendon interposition or ligament reconstruction

Scaphoid fractures are a common injury accounting for more than 58% of all carpal bone fractures(1,2). Biomechanical studies have suggested that scaphoid mal-union may lead to altered carpal contact mechanics causing decreased motion, pain and arthritis(1,2). The severity of mal-union required to cause deleterious effects has yet to be established. This limits the ability to define surgical indications or impacts on prevention of posttraumatic arthritis. Computed tomography has been shown to be a useful in determining the 3D implications of altered bony alignment on the joint contact mechanics of surrounding joints. The objective of this study was to report mid-term follow-up image-based outcomes of patients with scaphoid mal-unions to determine the extent to which arthritic changes and decreased joint space is present after a minimum of 4 years following fracture. Participants (n=14) who had previously presented with a mal-united scaphoid fracture (indicated by a Height:Length Ratio >0.6) between November 2005 and November 2013 were identified and contacted. A short-arm thumb spica case was used to treat X patients and X required surgical management. Baseline and follow-up CT images, were performed with the wrist in radial deviation and positioned such that the long axis of the scaphoid was perpendicular to the axis of the scanner. Three-dimensional inter-bone distance (joint space), a measure of joint congruency and 3D alignment, was quantified from reconstructed CT bone models of the distal radius, scaphoid, lunate, capitate, trapezium and trapezoid from both the baseline and follow-up scans(3). Repeated measures ANOVA was used to detect differences in contact area (mm2) between baseline and follow-up CT's for the radioscaphoid, scaphocapitate and scaphotrapezium-trapezoid joint. The average age of participants was 43.1 years (16–64 years old). There was significant loss of joint space, indicated by a greater joint contact area 3–4 years post fracture, between baseline and follow-up reconstruction models, at the scaphocapitate (mean difference: 21.5±146mm2, p=0.007) and scaphotrapezoid joints (mean difference: 18.4 ±28.6mm2, 0.042). Significant differences in the measured contact area was not found for the radioscaphoid (0.153) and scaphotrapezium joints (0.72). Additionally, the scaphoid, qualitatively, appears to track in the vorsal direction in the majority of patients following fracture. Increased joint contact area in the scaphocapitate and scaphotrapezoid joint 3–4 years following fracture results from decreased 3D joint space and overall narrowing. Joint space narrowing, while not significantly different for all joints examined, was reduced for all joints surrounding the scaphoid. Decreased joint space and increased contact area detectable within this short interval might be suggestive of a trajectory for developing arthritis in the longer term, and illustrates the potential value of these measures for early detection. Longer term follow-up and correlation to clinical outcomes are needed to determine the importance of early joint space narrowing, and to identify those most at risk

Introduction. From 2004 to 2015, elective lumbar fusions increased by 62% in the US. The largest increases were for among age 65 or older (139% in volume) and scoliosis (187%) [1]. Age is a well known factor of osteoporosis. The load-sharing may exceed the pedicular screws constructs in aging spine and lead to non-union and re-do. Surgical options may increase the screw purchase (e.g.: augmentation, extensions) at supplementary risks. Pedicular screw are known to cause vascular, nerve root or cord injuries. Facing these pitfalls, the surgeon's experience and rule of thumbs are the most deciding factors for the surgical planning. The aim of this study is to assess the accuracy of a patient specific tool, designed to plan a safe pedicular trajectory and to provide an intraoperative screw pullout strength estimate. Materials and Methods. Clinical QCT were taken for nine cadaveric spines (82 y. [61; 87], 6 females, 3 males). The experimental maximum axial pullout resistance (FMax) of twenty-seven pedicular screws inserted (nine T12, nine L4 and nine L5) was obtained as described in a previous study [2]. A custom 3D-WYSIWYG software simulated a medio-lateral surgical insertion technique in the QCTs coordinates reference, respecting the cortical walls. Repeatable density, morphometric and hardware parameters were recorded for each vertebrae. A statistical model was built to match predictive and experimental data. Preliminary results. Experimental FMax(N) were [104;953] (359 ±223). A further displacement of 1,81mm ±0,35 halved the experimental FMax. Predictive FMax(N) were [142;862] (359 ±220). A high positive correlation between experimental and predictive FMax was revealed (Pearson, ρ = 0.93, R2 = 0.87, p < .001, figure 1). Absolute differences ranged between 3N and 177N. Discussion. A high screw purchase in primary fixation is paramount to achieve spine surgical procedures (e.g.: kyphosis, scoliosis) and postoperative stability for vertebrae fusion. High losses of screw purchase by bone plastic deformation, begin with tiny pullouts. Theses unwanted intraoperative millimetric over-displacements are hard to avoid when monitoring at the same time tens of screws surrounded by bleedings. This advocates for including predictive FMax for each implantable pedicular screw in the surgical planning decision making process to prevent failures and assess risks. For the first time, this study presents an experimentally validated statistical model for FMax prediction with a safe trajectory definition tool, including patients’ vertebrae and hardware properties and referring to the patient's clinical 3D quantitative imagery. The model was able to differentiate between bone quality and vertebrae variations. More extensive model validation is currently ongoing to interface with robotics & navigation systems and to produce meshes for 3D printing of sterilizable insertion guides

Background. The trapeziometacorpal joint (TMJ) of the thumb is a common site of primary osteoarthritis. Pain, crepitis and instability secondary to subluxation are common symptoms associated with TMJ arthritis. Conservative therapy help to control symptoms however with time, many patients progress with pain, deformity and functional limitation. The goals of operative intervention are to restore stability and strength, decrease pain and to provide a functional range of motion. Francobal-prosthesis may fulfil these criterions. Technique. We implanted the prosthesis through a dorso-radial straight longitudinal or slightly curved skin incision. A dorsal capsulotomy is performed and at this step adduction deformity should be addressed. An osteotomy of the proximal surface of the first metacarpal is made perpendicular to the long axis of the medullary cavity followed by reaming of the medullary cavity and then a trial fit. This is followed by preparation of the trapezium including removing any osteophytes, drilling of a cavity. Dental burs may be used at this step to deepen the cavity. The process of cementation started by cementation of the cup with its opening neutral to the joint surface, and if there is any muscle tension, bone is removed from the metacarpal before the metacarpal component is cemented. Reduction is achieved by snapping. The capsule and wound are closed and the thumb is immobilised in an adduction splint for ten days. Results. Results showed marked improvement of pain in many patients with high rate of satisfaction. No restriction of movement or instability was observed. In some cases, loosening of the shaft was noticed. However, this does not affect the overall function. Discussion. De La Caffini`re-prosthesis presents one of the operative options in the management of trapeziometacorpal joint (TMJ). Arthritis, however, this operation is recommended only in selective cases where skaphoid-trapezium-trapezoid (STT) joints are not involved