Proximal Interphalangeal Joint Arthrodesis Research Articles

Influence of the biomechanical evaluation of rupture using two shapes of same intramedullary implant after proximal interphalangeal joint arthrodesis to correct the claw/hammer pathology: A finite element study.

We used finite element analysis to study the mechanical stress distribution of a new intramedullary implant used for proximal interphalangeal joint (PIPJ) arthrodesis (PIPJA) to surgically correct the claw-hammer toe deformity that affects 20% of the population. After geometric reconstruction of the foot skeleton from claw toe images of a 36-year-old male patient, two implants were positioned, in the virtual model, one neutral implant (NI) and another one 10° angled (10°AI) within the PIPJ of the second through fourth HT during the toe-off phase of gait and results were compared to those derived for the non-surgical foot (NSF). A PIPJA was performed on the second toe using a NI reduced tensile stress at the proximal phalanx (PP) (45.83 MPa) compared to the NSF (59.44 MPa; p < 0.001). When using the 10°AI, the tensile stress was much higher at PP and middle phalanges (MP) of the same toe, measuring 147.58 and 160.58 MPa, respectively, versus 59.44 and 74.95 MPa at corresponding joints in the NSF (all p < 0.001). Similar results were found for compressive stresses. The NI reduced compressive stress at the second PP (-65.12 MPa) compared to the NSF (-113.23 MPa) and the 10°AI (-142 MPa) (all p < 0.001). The von Mises stresses within the implant were also significantly lower when using NI versus 10°AI (p < 0.001). Therefore, we do not recommend performing a PIPJA using the 10°AI due to the increase in stress concentration primarily at the second PP and MP, which could promote implant breakage.

Biomechanical Analysis of Headless Compression Screw Versus Tension Band Wiring for Proximal Interphalangeal Joint Arthrodesis

Proximal interphalangeal (PIP) joint arthrodesis is a procedure employed to address arthritis, instability, and deformity. Multiple fixation methods are available to maintain stability across the arthrodesis interval, including headless compression screws (HCSs), tension band wiring (TBW), plating, and Kirschner wire constructs. The purpose of this study was to compare the biomechanical properties of the HCS and TBW techniques. Thirty-two nonthumb digits from the paired upper limbs of four fresh frozen cadavers were divided into pairs, matching contralateral digits from the same specimen. One PIP joint of each pair was fused with an antegrade 3.5 mm HCS, and the second was fused with TBW using 0.035 in. Kirschner wires with 24-gauge dental wire. Each construct was then stressed to 10 N in the radial deviation, ulnar deviation, flexion, and extension planes, and stiffness (N/mm) was calculated. The fingers were stressed to failure in extension with the ultimate load and mode of failure recorded. When stressed in extension, the HCS construct had a significantly greater mean stiffness than the TBW construct (16.4 N/mm vs 10.8 N/mm). The stiffness in all other planes of motion were similar between the two constructs. The mean ultimate load to failure in extension was 91.4 N for the HCS and 41.9 N for the TBW. The most common mode of failure was fracture of the dorsal lip of the proximal phalanx (13/16) for the HCS and bending of the K-wires (15/16) for TBW. Arthrodesis of the PIP joint using a HCS resulted in a construct that was significantly stiffer in extension with greater than double the load to failure compared to TBW. Although the stiffness required to achieve successful PIP joint arthrodesis has not been well quantified, the HCS proved to be the most favorable construct with respect to initial strength and stability.

Surgical Treatment of Metatarsalgia and Severe Instability of Lesser Metatarsophalangeal Joints

The main object of this prospective cohort study was to compare surgical treatment options for primary metatarsalgia and the severe instability of lesser metatarsophalangeal joints. The outcomes of triple Weil osteotomy combined with direct plantar plate repair and triple Weil osteotomy, performed with proximal interphalangeal joint arthrodesis, are analyzed and compared. One hundred thirteen patients (117 feet) were enrolled in the study. They were split into 2 groups. In the first group, undergoing Weil osteotomy, combined with the plantar plate repair, good results, including complete pain reduction, elimination of hyperkeratosis, and American Orthopedic Foot and Ankle Society Score improvement, were achieved in 84.7% of the cases. The second group, where the combination of Weil osteotomy and proximal interphalangeal joint K-wire arthrodesis was used, demonstrated good results in 52.4% of the cases. Weil osteotomy, combined with the plantar plate repair, achieves better results in comparison to osteotomy, performed with the interphalangeal joint arthrodesis.

An effective aesthetic toe-shortening procedure

Background Many people with a longer second toe or lesser toes experience symptoms such as corns, hammertoe, and numerous others, especially when wearing open-toe shoes. Proximal interphalangeal joint arthrodesis using intraosseous loop wiring performed through a hidden side incision is a useful method to shorten the lesser toes aesthetically.Methods Aesthetic toe-shortening procedures were performed in 30 patients. All patients were evaluated by a physical examination and X-rays, and they underwent proximal interphalangeal joint arthrodesis using intraosseous loop wiring through a medial incision. Demographic characteristics, including foot morphology, were analyzed. The number of resected toes and resection amounts of each toe were measured. Patients’ satisfaction was determined through a questionnaire administered at each follow-up.Results In total, 91 toe-shortening procedures were performed in 30 patients who were followed up for an average of 24 months (range, 6–48 months). Sixteen patients had Greek-type feet (53.3%) and 14 had square-type feet (46.7%). Twelve patients had hammer toe deformity (40.0%) and 13 had corns (43.3%). The average length of the resected second and third toes was 9.66±2.79 mm (range, 5–15 mm) and 7.78±2.51 mm (range, 5–12 mm), respectively. The vast majority of patients were satisfied with the final results. No significant complications such as nonunion occurred. Only one case of mild angulation of the second toe was noted.Conclusions Aesthetic toe-shortening using the procedure described here can prevent the development of lessor toe deformities and provide permanent, aesthetically pleasing results with a short recovery time.

Clinical and Radiographic Results of a Dual-Component Intramedullary Implant for Hammer Toe Deformity in Patients with Rheumatoid Arthritis

Objectives: Clinical and radiographic results of proximal interphalangeal (PIP) joint arthrodesis using a dual-component intramedullary implant for rheumatoid arthritis (RA) forefoot deformities have not been reported. Thus, the outcomes of this implant were investigated.

Proximal Interphalangeal Joint Arthrodesis of the Hand Utilising a Rigid Intramedullary Device.

The proximal interphalangeal joint (PIPJ) is critical for proper finger and hand function. Arthritis of this joint can lead to significant pain and functional impairment. The APEX IP® Extremity Medical fusion device (Extremity Medical, Parsippany, New Jersey, USA) is an interlocking intramedullary screw device that provides a reliable method of hand PIPJ arthrodesis with good patient outcomes. We describe an easily reproducible surgical technique guide for using this device. Level of Evidence: Level V (Therapeutic).

Minimally Invasive Arthrodesis of the Equine Proximal Interphalangeal Joint: A Biomechanical Comparison of Three 5.5-mm Cortical Screws Inserted in Lag Fashion and Two 7.0-mm Headless Cannulated Dual-Pitch Compression Screws.

The aim of this study was to compare the biomechanical properties of two minimally invasive arthrodesis techniques of the equine proximal interphalangeal (PIP) joint (three transarticular 5.5-mm cortical screws [AO-3TLS] vs. two transarticular 7.0-mm headless cannulated multi-use compression screws [MUC-2TS]) in dynamic non-destructive testing and compression testing to failure. The experimental study included six pairs of cadaveric adult equine forelimbs; one limb from each horse was randomly assigned to one of the treatments, and the contralateral limb was submitted to the remaining treatment. The dynamic test was performed alternating non-destructive compression tests at a displacement rate of 5 mm/min up to 5,000 N and sinusoidal compressive cyclic tests at 6 Hz, using a 3,600-N amplitude for 8,550 cycles. Construct stiffness and maximum sagittal plane rotation about the PIP joint markers were determined during the dynamic test. After the dynamic test reached 136,800 cycles, the monotonic compressive test until failure was performed on each construct: load, displacement and sagittal plane rotation about the PIP joint marker at failure were analysed. The evaluated biomechanical properties showed no statistical difference between the AO-3TLS and MUC-2TS treatment groups in any of the ramps of the dynamic non-destructive test and in the compression loading until failure test. The MUC-2TS treatment produced biomechanical properties equivalent to the AO-3TLS treatment for PIP joint arthrodesis.

Hammer Toe Correction with Proximal Interphalangeal Joint Arthrodesis.

First described by Soule in 1910, arthrodesis of the proximal interphalangeal joint is a common operative method of treatment of hammer toe, or fixed-flexion deformity of the proximal interphalangeal joint of the lesser toes1. The deformity is often caused by imbalance in intrinsic and extrinsic muscle function across the interphalangeal joint and metatarsophalangeal joint2,3, which can be effectively addressed through proximal interphalangeal joint straightening and arthrodesis in conjunction with soft-tissue balancing of the metatarsophalangeal joint. Following longitudinal skin incision over the joint, a transverse extensor tenotomy and capsulotomy reveal the proximal interphalangeal joint and provide appropriate exposure of the head of the proximal phalanx. With the soft tissues protected, the proximal and middle phalanges undergo resection of the articular surfaces to allow osseous apposition. This step can be performed with a rongeur sagittal saw or with osteotomes4,5. The head of the proximal phalanx is resected proximal to the head-neck junction, and the proximal portion of the middle phalanx is removed to expose the subchondral bone. Often, there is a dorsal contracture of the metatarsophalangeal joint that is elevating the toe, which is addressed with use of a longitudinal incision over the metatarsophalangeal joint, a Z-lengthening of the long extensor tendon to the toe, and a subsequent capsulectomy. If there is an angular component to the deformity, the collateral ligaments are released from the metatarsal neck, and the toe can be balanced. If there is residual subluxation of the joint that is incompletely corrected by soft-tissue procedures, a metatarsal osteotomy should be considered. Fixation is then performed with use of a smooth Kirschner wire. The wire is inserted from the middle phalanx out the tip of the toe and subsequently inserted retrograde across the proximal interphalangeal joint, often into the metatarsal head and neck, holding the metatarsophalangeal joint in appropriate position. This step can also be completed with use of novel methods including screws, bioabsorbable pins, or intramedullary implants6-8. Nonoperative treatments for hammer toe deformity are generally pursued prior to surgery and include shoe modifications such as a wide toe-box, soft uppers, and padding of osseous prominences3,9,10. Alternative surgical treatments include proximal interphalangeal arthroplasty, soft-tissue capsulotomy, extensor tendon lengthening, and amputation11. Although nonoperative treatment can alleviate symptoms temporarily, surgical treatment is often necessary for definitive treatment of hammer toe. Soft-tissue procedures such as tendon lengthening can provide a stabilizing benefit, but the degenerative bone changes associated with hammer toe are better addressed with use of resection of the proximal interphalangeal joint3. Arthroplasty allows for some retained motion; however, this motion may lead to deformity and pain over time2. Arthrodesis provides less painful and more reliable fixation as well as equal outcomes compared with other operative techniques. Patient satisfaction rates after this procedure are high, with pain relief in up to 92% of patients and rare complications7-12. Outcomes of this procedure are favorable, with rates of osseous fusion ranging from 83% to 98%2,4,11,13. Patient satisfaction rates range from 83% to 100%4,11. Historically, patients have expressed dissatisfaction with pain and the appearance of exposed hardware, but novel internal fixative devices provide a more natural appearance to the toe without the need for secondary surgical procedures for pin removal8,14. Patients are often able to return to regular activity at 6 weeks postoperatively; however, there may be persistent pain or swelling in the toe. Wide shoes and activity modifications are frequently continued for several more weeks postoperatively, and some patients may benefit from formal physical therapy and at-home rehabilitation. Avoid vascular compromise by ensuring adequate resection of bone at the proximal interphalangeal joint.A longitudinal incision across the joint provides greater exposure but can lead to scar contracture that elevates the toe. One alternative is the use of an elliptically shaped incision over the proximal interphalangeal joint, which can improve cosmesis but does restrict exposure.Excessive osseous resection can lead to a cosmetically undesirable short toe.If using an implant for the arthrodesis, ensure the implant is not too big for the toe. Most implants are too big for fifth-toe arthrodesis.In toes with severe deformity, fixation with a Kirschner wire is often preferred because excessive stretching of the neurovascular bundle can lead to toe compromise and if Kirschner wire is used the pin can easily be removed at bedside.For flexible deformities, a nonoperative approach is recommended, such as stretching exercises, shoe-wear modifications, and metatarsal pads. A tenotomy of the flexor digitorum brevis is a soft-tissue procedure that can be considered if nonoperative treatment is insufficient to correct the deformity. If flexor digitorum brevis tenotomy does not adequately treat proximal interphalangeal joint deformity, a proximal interphalangeal joint arthrodesis should be the next step. MTP = metatarsophalangealPIP = proximal interphalangeal.

Functional evaluation of optimal index finger proximal interphalangeal joint fusion angle using a simulated joint arthrodesis

This study aims at qualitatively and quantitatively evaluating the effects of simulated index finger proximal interphalangeal (PIP) joint fusion angles on hand kinematic function and performance. Although arthrodesis of the index finger PIP joint is an effective medical procedure that produces a durable, pain-free, and stable joint, it permanently immobilizes the joint. Twenty healthy subjects performed basic functional hand activities with the index finger PIP joint unconstrained (UC) and constrained to selected angles under surveillance of a motion capture system. Our results indicate differences in perceived difficulty, time performance, and the functional ROM of the hand joints when the index finger PIP joint is UC and constrained to 0, 20, and 40 degrees of flexion. The mean total perceived difficulty scores for all 6 tasks were higher for the PIP at 0 degrees than for the UC condition (p < 0.001) and for the PIP at 40 degrees (p = 0.048). The functional ROM presented a smaller total number of hand joints affected by the PIP at 20 degrees (25 in total) than the PIP at 0 (31 in total) and 40 (27 in total) degrees during execution of all 6 tasks tested. Therefore, the decision on the appropriate index finger PIP angle for arthrodesis may be between 20 and 40 degrees, as globally for all 6 tasks tested, 0 degrees exhibited the worst results regarding perceived difficulty, performance time, and number of joints with affected ROM. Selecting the appropriate angle for arthrodesis should consider a more complete set of functional activities.

Biodegradable fixation pins for interphalangeal joint arthrodesis in lesser toe deformity and fracture correction – A retrospective follow-up of 31 toes

Lesser toe deformities are commonly surgically treated with interphalangeal joint arthrodesis using different internal fixation implants with good results. There are few studies reporting the results of the use of bioabsorbable implants. The aim of this study was to investigate the clinical and radiological outcomes of lesser toe interphalangeal joint arthrodesis using a novel biodegradable pin as fixation method. Consecutive patients operated by proximal (PIPJ) or distal interphalangeal joint (DIPJ) arthrodesis using the Inion FreedomPin™ (Inion Oy, Tampere, Finland) with a minimum of 12 months of follow-up were retrospectively evaluated both clinically and radiologically. 21 patients (age 34–78, median 60 years) with 24 feet and 31 toes were available with a median follow-up of 26 (range 12–40) months. Clinical alignment was good in all but one toe. There were no complications and patient satisfaction was high. The radiological alignment was corrected in 25, partially corrected in five, and not corrected in one toe. A complete radiological bony fusion was detected in 25 (81%), partial in one (3%), and no fusion in five (16%) toes. In conclusion, the Inion FreedomPin™ bioabsorbable pin had clinically and radiologically favourable outcome for lesser toe interphalangeal joint arthrodesis.

Intraosseous Technique for Correction of Hammertoe Deformity.

Hammertoe deformities are among the most common conditions treated by foot and ankle surgeons. Many different types of proximal interphalangeal joint arthrodesis fixation techniques have been used. These include implant fixation, absorbable fixation, screw fixation, two-pin fixation, and single-Kirschner wire fixation. Each of these has their own set of associated advantages and disadvantages. One of the most common techniques to address hammertoe deformity is the use of Kirschner wires. Although Kirschner wires have been reliable and produced good outcomes, there are some drawbacks associated with their use. Some disadvantages include wire failure (bending/breaking), infection, and patient anxiety associated with removal. One of the more challenging aspects with using a single Kirschner wire for fixation is stability. Pistoning and rotational instability may occur with single-Kirschner wire use. Both pistoning and lack of rotational control can lead to nonunion, fibrous union, malunion, and ultimately patient dissatisfaction. The suturedesis technique is a surgical option that may be considered when a surgeon attempts to address these disadvantages. The authors believe this technique can adequately bring stability to the frontal plane and eliminate pistoning, which may lead to better fusion rates, better postoperative alignment, and better patient satisfaction. This article outlines the authors' surgical technique of suturedesis in correcting hammertoe deformity.

Fiber-reinforced fixation implant for proximal interphalangeal joint arthrodesis shows advanced implant bio-integration at 2-year follow-up

BackgroundA bio-integrative fiber-reinforced implant (OSSIOfiber® Hammertoe Fixation Implant, OSSIO Ltd., Caesarea, Israel) for proximal interphalangeal joint (PIPJ) correction-arthrodesis showed partial bio-integration at 1-year follow-up (1FU) in a previous study. The study was prolonged to assess the bio-integration at 2-year-follow-up (2FU). MethodsTwenty-four patients with proximal interphalangeal joint (PIPJ) correction-arthrodesis using the fiber-reinforced implant and analysed at 1FU, completed 2FU. Follow-up included clinical examination, patient reported outcomes, radiographs, MRI and bio-integration scoring. Results were compared between the 1FU and 2FU (paired t-test). ResultsRadiographs confirmed fusion in 96 % (n = 23) at 2FU (1FU, 92 % (n = 22)). Implant was no longer visible in 21 % (n = 5), partially visible in 33 % (n = 8), and fully visible in 46 % (n = 11)(1FU, fully visible 100 % (n = 24)). The border between implant and surrounding bone was scored not visible in 88 % (n = 21) and partially visible in 12 % (n = 3) (1FU, border partially visible 100 % (n = 24)). There were no cyst formation or fluid accumulation findings 1FU/2FU. Mild bone edema was detected in 4 % (n = 1) (1FU, 29 % (n = 7)). None of the edema findings were considered as adverse implant related. The mean bio-integration score was 9.71 ± 0.69 at 2FU (1FU, 7.71 ± 0.46). The parameters of border between implant and bone and bone edema further improved at the 2FU compared to the 1FU, total bio-integration score was also higher at 2FU than 1FU (each p < 0.05). ConclusionsThis study demonstrates 96 % PIPJ fusion rate and increased bio-integration from 1FU to 2FU, reaching advanced bio-integration of the fiber-reinforced implant at 2FU.

Evaluation of factors associated with surgical site infection in equine proximal interphalangeal joint arthrodesis: 54 cases (2010-2019).

BackgroundThe frequency of surgical site infection (SSI) following orthopaedic implant placement in horses has been reported but not compared with respect to specific antibiotic protocols administered.ObjectivesTo determine factors associated with SSI in horses undergoing proximal interphalangeal joint (PIPJ) arthrodesis including perioperative antibiotic protocols.MethodsRecords were evaluated (2010–2019), and horses undergoing PIPJ arthrodesis were identified. Patient signalment, supervising surgeon, reason for surgery, limb, implants placed, anaesthetic time, duration casting/coaptation postoperatively, antibiotic regimen and incidence/onset SSI were recorded. Bayesian and frequentist logistic regressions were used to estimate the contribution of covariates to infection occurrence.ResultsFifty‐four PIPJ arthrodeses were performed. SSI occurred in 2/54 (3.7%) on day 15,30. Arthrodesis was performed most commonly for osteoarthritis (33/54, 61.1%), fracture (11/54, 20.4%), and subluxation (5/54, 9.3%). Perioperative systemic antibiotics were administered 1–3 days (15/54, 27.8%) or > 3 days (39/54, 72.2%). Antibiotic protocols included cefazolin/gentamicin (20/54, 37%), cefazolin/gentamicin/doxycycline (14/54, 25.9%) and potassium penicillin/gentamicin (10/54, 18.5%). Regional limb perfusion was performed preoperatively 31/54 (57.4%) and postoperatively 7/54 (13%). Survival to dismissal was 98.1% (53/54 horses) with one horse euthanized due to support limb laminitis. No association was identified between antibiotic selection or duration (1–3 vs. > 3 days), pre‐operative regional antibiotic perfusion, intraoperative antibiotic lavage or anaesthetic time (< or > 3 h) and SSI; however, modelling was complicated by quasi‐complete or complete separation of the data. Bayesian analysis (but not frequentist analysis) indicated an association between post‐operative regional antibiotic perfusion and SSI. Limitations include the retrospective nature of data collection and the low rate of infection overall.ConclusionsThe prevalence of SSI in this population was lower than that in previous reports of equine orthopaedic internal fixation. There was no difference in SSI rate in cases administered systemic antibiotics for 1–3 days or >3 days, or for those horses that did or did not receive preoperative regional antibiotic perfusion.

Comparison of Lesser Toe Proximal Interphalangeal Joint Arthrodesis Versus Resection Arthroplasty: A Randomized Controlled Study.

The goal of this study was to compare operative outcomes after lesser toe deformity correction with either proximal interphalangeal (PIP) joint arthrodesis or PIP joint resection arthroplasty. A prospective randomized controlled trial was performed with 37 patients (48 toes) operated on with one of these two procedures. Evaluation of the numeric rating scale score, the American Orthopedic Foot and Ankle Society score, osseous consolidation, and clinical outcome was performed preoperatively and at 6 weeks and 6 months postoperatively. Both study groups showed significant improvement at 6 months postoperatively. Although osseous consolidation was significantly higher for the arthrodesis group (P=.001), this difference did not affect clinical outcomes, and at 6 months postoperatively, pain on the numeric rating scale was 0 (range, 0-7) for the arthroplasty group and 0 (range, 0-5) for the arthrodesis group (P=.669). The American Orthopedic Foot and Ankle Society score was 83 (range, 39-95) and 80 (range, 59-95), respectively (P=.879). No difference was observed for signs of inflammation or axis correction. Even a direct comparison of toes with radiologically osseous fusion (n=16) with those without fusion (n=32) did not show any clinical differences. This randomized controlled study showed no clinical differences in outcome between PIP joint arthrodesis and PIP joint resection arthroplasty for correction of lesser toe deformities, with good to excellent outcomes for both groups. [Orthopedics. 2022;45(2):86-90.].

Proximal interphalangeal locking compression plate for pastern arthrodesis in horses.

Outcomes following proximal interphalangeal joint (PIPJ) arthrodesis by a variety of surgical methods are available. Reports detailing clinical outcomes following PIPJ arthrodesis utilising the proximal interphalangeal joint locking compression plate (PIP-LCP) and abaxial transarticular lag screws technique are limited. To report survival, radiographic and clinical outcomes following PIPJ arthrodesis with PIP-LCP and abaxial transarticular lag screw fixation. Retrospective case series. Medical records of all horses undergoing pastern arthrodesis from 2009 to 2018 were reviewed. Arthrodeses performed using a 3-hole, 4.5mm narrow LCP, specifically designed for the proximal interphalangeal joint, were included. Patient details, presentation, radiographic findings, intraoperative and post-operative data, and complications were documented. Short- and long-term follow-up was available for 23 horses. Thirty PIPJ arthrodeses were performed in 29 horses meeting the criteria for inclusion. Twenty-eight horses (97%, 95% CI 83-100) survived to discharge. Twenty-three horses (79%, 95% CI 60%-92%) had successful outcomes including 12 of the 15 forelimb cases and 11 of the 13 hindlimb cases with available follow-up. Fifteen of 19 performance horses returned to athletic activity. Soundness in performance horses was recognised at less than 3months in one case, 3 to 6months in six cases, 6 to 12months in five cases, and greater than 12months in six cases. Complications included three implant infections, support limb laminitis (two horses), and fragmentation of the extensor process of the distal phalanx (one horse). A retrospectively reviewed, small study population with a variety of breeds and disciplines. The PIP-LCP construct provides a very good prognosis for performance and an excellent prognosis for pasture soundness.

Fiber-reinforced fixation implant for proximal interphalangeal joint arthrodesis shows implant bio-integration at 1-year follow-up

BackgroundA new bio-integrative fiber-reinforced implant (OSSIOfiber® Hammertoe Fixation Implant, OSSIO Ltd., Caesarea, Israel) was developed for proximal interphalangeal joint (PIPJ) correction-arthrodesis. The main purpose of this clinical study was to assess implant bio-integration at 1-year follow-up. MethodsTwenty-four patients, previously treated for a Hammertoe deformity using the bio-integrative, fiber-reinforced implant, were enrolled in this follow-up study. One-year follow-up included clinical examination, patient reported outcomes, radiographs, Magnetic Resonance Imaging (MRI) and bio-integration scoring. ResultsProximal interphalangeal joint (PIPJ) radiographic fusion rate was 92% (n = 22). MRI was analyzed for 24 (100%) patients. In 100% of patients (n = 24), the border between implant and surrounding tissue was scored as partially visible. There were no cyst formation or fluid accumulation findings. Mild bone edema was detected in 29% (n = 7) and is attributed to the chronic distribution of forces due to chronic abnormal gait and pasture. None of the edema findings were considered as adverse implant-related finding. The mean bio-integration score was 7.71 ± 0.46. ConclusionsThis study demonstrates safe bio-integration of the newly developed fiber-reinforced implant at 1-year follow-up without negative side effects.

The Comparison of Latero-Medial versus Dorso-Palmar/Plantar Drilling for Cartilage Removal in the Proximal Interphalangeal Joint.

Simple SummaryArthrodesis of the proximal interphalangeal joint consists of the assisted fusion of the proximal and middle phalanges. The main indications for performing arthrodesis in equine patients are chronic osteoarthritis unresponsive to medical treatment, articular fractures, luxation and subluxation. This procedure can allow a return to athletic career in selected cases, or free the animal from chronic pain in others. Arthrodesis is performed through two basic steps: articular cartilage removal and bone immobilization. Whereas several methods have been studied to achieve the second one, little has been investigated for cartilage removal. The most utilized technique consists of disarticulating the joint to remove the cartilage. Other techniques have been investigated to remove enough cartilage to allow bone fusion and reduce the invasiveness of the procedure. The aims of this work were to assess the capability of a lateral drilling approach to the joint to remove a sufficient amount of cartilage, and compare it to the previously proposed dorsal drilling approach. The lateral drilling approach, especially when performed under digital fluoroscopy, turned out to be more efficient in articular cartilage removal in the proximal interphalangeal joint.The aims of the present study were to compare the percentages of articular cartilage removed using a lateral drilling approach of the proximal interphalangeal joint (PIPJ) and a dorsal drilling approach, and to assess the usefulness of digital fluoroscopy when performing a lateral drilling approach. Sixty cadaveric PIPJs were drilled using a surgical drill bit to remove the articular cartilage. The limbs were divided into three groups containing 10 forelimbs and 10 hindlimbs each. One group received the dorsal drilling approach, the second one received the lateral drilling approach and the last one received the lateral drilling approach under digital fluoroscopy guidance. The percentage of articular cartilage removed from each articular surface was assessed using Adobe Photoshop ® software. The percentages of removed cartilage turned out to be significantly higher with lateral approach, especially under fluoroscopic guidance, both in the forelimbs (p = 0.00712) and hindlimbs (p = 0.00962). In conclusion, the lateral drilling approach seems to be a minimally invasive technique with which to perform PIPJ arthrodesis, even more efficient than the previously reported dorsal approach.

Relative Strengths of Intramedullary K-Wire Techniques for Digital Deformities

Hammertoe deformity correction surgery is one of the most common procedures performed by foot and ankle surgeons. Recent foot and ankle medical literature presents conflicting opinions regarding the optimal intramedullary fixation device and techniques for use in digital deformity correction. There are a number of varying fixation constructs of intramedullary Kirschner wire fixation reported for proximal interphalangeal joint arthrodesis; however, there are no reports of relative loading strength of the fixations. In this study, 90 sawbone models were divided equally into 3 groups of different intramedullary Kirschner wire fixation techniques: Group A- single straight, Group B- single bent, Group C- double bent. Each fixation construct underwent controlled axial loading and failure points were observed. Results showed no significant difference in load failure from all 3 groups with mean maximum force of Group A = 20N, Group B = 19.1N, and Group C =17.5N. We conclude that all Kirschner wire fixation options for digital deformity correction, will provide similar resistance to sagittal plane axial loads.

Proximal interphalangeal joint arthrodesis in horses: concepts, indications, and techniques

Surgical arthrodesis is effective for treating proximal interphalangeal joint (PIJ) injuries in horses. Despite several techniques described so far, the use of a 3-hole, 4.5mm-locking compression plate, associated with two 5.5-mm transarticular cortex screws, is currently considered the “gold standard.” This review describes the anatomy of the pastern, as well as causes, indications, and possibilities for arthrodesis in the equine PIJ. A description of the current surgical technique for joint fixation is also presented.

Proximal interphalangeal joint arthrodesis in a case of chronic proliferative osteoarthritis in the horse – a case report

Proximal interphalangeal joint (PIPJ) arthrodesis is performed commonly in horses with chronic osteoarthritis of the pastern joint or in cases of acute traumatic injury to the pastern, in which the weight-bearing bony column must be restored. Chronic osteoarthritis of the pastern joint is a frequent cause of lameness in the equine athlete and is evidenced by chronic lameness which is supported radiographically by periosteal proliferation and loss of joint space. The conventional method of joint fusion involves the opening of the joint, debridement of the joint cartilage, osteostixis of the subchondral bone plate and application of either lag screws or plate. This case report describes the successful treatment of chronic proliferative ossified osteoarthritis and periarthritis of the proximal interphalangeal joint of the front limb of two mares by performing simple percutaneous drilling destruction of the articular cartilage and stabilization with the application of three lag screws. After three years of conservative treatment with local corticosteroids, the mares exhibited non-weight-bearing lameness. Radiographs revealed extensive periarticular new bone formation over the proximal interphalangeal joint. Three 4.5 mm transcortical bone screws were placed in the lag fashion. A lower limb fiberglass cast was applied in both cases for 3 days. The antibiotic and analgesic protocol included gentamicin, penicillin, and flunixin meglumine for several days. Control radiographic examination after a period of 6 and 12 months showed reduction of the periarticular bone tissue. Both of the mares in this case study successfully returned to pleasure riding after undergoing forelimb arthrodesis.