Use of a headless compressive screw for distal interphalangeal joint arthrodesis in digits: clinical outcome and review of complications

PURPOSE: Arthrodesis of the distal interphalangeal joint (DIPJ) or thumb interphalangeal joints can be necessary to treat pain, deformity, or instability associated with arthritis. Compression and rigid fixation are thought to influence fusion rates and time to union favorably. The purpose of the study was to review the clinical outcome and complications associated with the use of a fully threaded headless compression screw for DIPJ arthrodesis. METHODS: Twenty-seven distal interphalangeal or thumb interphalangeal fusions were performed with an axial Mini-Acutrak screw in 22 patients. Charts, surgical reports, and preoperative and postoperative x-rays were reviewed to determine the incidence, time to union, and complications. The minimal follow-up period was 3 months. RESULTS: Twenty-three of the 27 arthrodeses achieved bony union. Complications included symptomatic nonunion (n=1, treated with secondary fusion), asymptomatic nonunion (n=2, left untreated), infection (n=4; 2 patients required implant removal that resulted in nonunion but declined revision) and nail bed injury (n=3). CONCLUSIONS: The Mini-Acutrak screw technique achieves healing rates that are comparable with but not superior to other techniques. Its main advantages are ease of execution, fully buried hardware, and early mobilization; however, the procedure is associated with complications and meticulous technique is required to avoid them. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic, Level IV.     

Comparison of Initial Compression Force Across the Subtalar Joint by Two Different Screw Fixation Techniques

The purpose of this study was to compare the magnitude of compressive force across the posterior facet of the subtalar joint between 2 different screw orientations in a simulated subtalar fusion model fixated with cannulated 7.3-mm screws. Eight paired fresh, frozen cadaver feet were used. Before testing, the bone mineral density of the calcanei and tali was measured with dual energy x-ray absorptiometry to ensure comparable bone mineral density. The paired cadaver calcanei and tali were noted to have less than .05 g/cm(2) difference in bone mineral density. The paired specimens were each randomly assigned to 1 of 2 methods of fixation across the subtalar joint: a plantar approach, where the screw was oriented vertically from the plantar aspect of the calcaneus, distal to the tuberosity; and a posterior approach, where the screw was oriented obliquely from the posterior calcaneal tuberosity. A load-sensing washer was placed under the cancellous screw head before insertion of the screw to measure the magnitude of the compression force across the simulated fusion site. The mean compression force for the posterior-to-anterior approach was 581 N, with a standard deviation of 242 N. The mean force for the plantar-to-superior approach was 604 N, with a standard deviation of 276 N. The compression force obtained by the 2 approaches was not significantly different (P = .74). The plantar-to-superior fixation technique represents an alternative subtalar arthrodesis technique to the posterior-to-anterior approach, potentially allowing one to revise a previously failed arthrodesis when the standard fixation techniques cannot be applied.     

A comparison of outcomes of posterior arthroscopic subtalar arthrodesis with or without bone graft for treatment of subtalar arthritis

BackgroundIt remains unclear whether to perform a bone graft is necessary during posterior arthroscopic subtalar arthrodesis. The present research aimed to comparatively analyze the outcomes of arthroscopic subtalar arthrodesis through a 3-portal posterior approach with or without bone graft.MethodsA total of 93 patients with subtalar arthritis who underwent posterior arthroscopic subtalar arthrodesis were retrospectively examined. The patients were divided into two groups according to whether they received bone graft or not. The clinical outcomes were compared for analysis.ResultsAmong the 93 patients included, 53 received bone graft and 40 did not. The union rate and time to osseous fusion suggested no significant difference between the two groups. The improvement of clinical outcomes were comparable between the two groups at the final follow-up.ConclusionsIn the present study, bone graft could not effectively reduce the risk of nonunion and improve the outcome.     

Comparison of pullout strength of small-diameter cannulated and solid-core screws

The purpose of this study was to determine the difference in pullout strength between cannulated and solid-core small-diameter bone screws. Cannulated screws from different manufacturers were compared against solid-core screws with 2.0-mm, 2.4-/2.5-mm, and 3.0-mm diameters. A synthetic material made to simulate bicortical bone was used as the test medium. The screws were extracted under servohydraulic control. There was no statistically significant difference between any of the cannulated and solid-core 2.0-mm screws used in this study (P < .05). In the 2.4-/2.5-mm screw tests, both of the cannulated screw designs had a significantly higher pullout strength when compared with the solid-core screw (P < .05). In the testing of 3.0-mm screw test, 1 of the cannulated screw designs showed a significantly higher pullout strength than the other cannulated and solid-core screws that were tested (P < .05). The results of this study suggest that small-diameter cannulated bone screws are similar in mechanical pullout strength to solid-core screws.     

Primary subtalar arthrodesis for the treatment of comminuted intra-articular calcaneal fractures

We report the short- and mid-term results in six patients (seven feet) affected by markedly comminuted intra-articular calcaneal fractures (Sanders type IV), treated by primary subtalar arthrodesis. The average age at surgery was 40 years. In all patients, arthrodesis of the subtalar joint was performed using a limited lateral approach to the calcaneus; it was stabilised with two or three cannulated screws. No patient had a preliminary reduction and internal fixation of the fracture. The time from injury to surgery averaged 20 days because all of the patients had associated visceral and/or other skeletal injuries. All of the patients were followed up clinically and radiographically 2 times, at an average of 12 months and 53 months after surgery. At the short-term follow-up, the mean AOFAS score was 70 points; the X-rays showed a complete fusion of the subtalar joint in all seven feet, without any sign of osteoarthritis of the calcaneo-cuboid and the talo-navicular joints. In all cases, an altered shape of the calcaneus was present. At the mid-term follow-up, the mean AOFAS score increased to 85 points; in one patient, radiographic signs of osteoarthritis of the calcaneo-cuboid and the talo-navicular joints were present and, in another patient, only talo-navicular joint was present, although both patients were free from pain. The difference between the two AOFAS scores was statistically significant. We believe that primary subtalar arthrodesis performed for markedly comminuted Sanders type IV calcaneal fractures yielded good mid-term results, and it is especially indicated when surgical treatment is delayed for whatever reason. A preliminary open reduction and internal fixation to restore the normal height of the calcaneus before performing the subtalar arthrodesis, as suggested by several authors, does not seem indispensable to obtain good clinical results.     

The results of Grice Green subtalar arthrodesis of valgus foot in spina bifida

Background:

Valgus foot is a common foot deformity in spina bifida. The most popular operation for the valgus deformity has been the Grice talocalcaneal blocking. It has not been studied primarily in children with spina bifida. We report a prospective series, we present the results of hind foot valgus deformity of children with spina bifida, using Grice talocalcaneal arthrodesis with a tricortical iliac bone graft.

Materials and Methods:

Between May 2000 and December 2003, 21 patients with bilateral (42 feet) valgus deformity of feet underwent surgery. There were 7 males and 14 females. The mean age of patients was 67.7 months (range 50–108 months).

Results:

The total number of feet that had nonunion was 11, in 7 of them the grafts were completely reabsorbed and the outcome of all these feet was unsatisfactory. Four feet had partial union of which three had unsatisfactory and one had satisfactory outcome. Sixteen feet had residual valgus deformity at the last followup visit, 10 patients had nonunion, and 6 had inadequate correction. Mean preoperative talocalcaneal and calcaneal pitch angles were 48.5° and 31.9°, respectively, which decreased to 38.5° and 29.1°, respectively, postoperatively. The decrease in talocalcaneal angle and calcaneal pitch was significant between preoperative and postoperative measurements (P<0.05).

Conclusion:

Grice subtalar arthrodesis technique is still a valuable option for valgus foot in patients with spina bifida. In this study, we found more encouraging results in older patients.     

Osteoid osteoma causing subtalar joint arthralgia: A case report

The authors describe a juvenile patient with an osteoid osteoma in the foot-a relatively rare location for this type of lesion. The appearance of this lesion in a juxtaarticular location is even more rare. An 11-year-old boy with a 6-month history of limping secondary to subtalar joint pain presented with a juxtaarticular osteoid osteoma located within the calcaneus. The lesion was present beneath the sinus tarsi and the subtalar joint region. Plain radiographs showed equivocal changes; however, magnetic resonance imaging clearly showed a central nidus. The lateral aspect and midbody of the calcaneus showed a spherical focus of diminished signal on both the T1- and T2-weighted images. This focus had a surrounding rim of significantly diminished signal on all sequences. Thus, findings were most consistent with an osteoid osteoma, although a Brodie abscess could not be ruled out. Surgical excision was performed and led to complete resolution of pain and limping. The pathology report confirmed the diagnosis of osteoid osteoma.     

Alternative to the distal interphalangeal joint arthrodesis: lateral approach and plate fixation

PURPOSE: Several fixation techniques for distal interphalangeal (DIP) joint arthrodesis have been described, with good clinical results and complication rates between 10% and 20%. We propose an alternative technique and fixation method using a lateral approach and 1.3-mm plate and screws fixation. METHODS: Between March and September 2005, 11 patients, totaling 15 fingers, had DIP joint arthrodesis by the described technique. The indications were posttraumatic arthritis in 8 fingers, degenerative or rheumatoid arthritis in 5 fingers, and isolated flexor digitorum profundus tendon lesions in 2 fingers. Patients were analyzed for osseus union, pain relief, and functional mobility of the finger. RESULTS: Arthrodesis relieved pain and restored stability at the 12th week, on average, with osseous union in all patients. All patients maintained full proximal interphalangeal joint motion with pulp-to-palm distance of zero at 6 months of follow-up evaluation. There were no rotational or angular deformities, nail bed lesions, or skin complications. CONCLUSIONS: The lateral approach with plate and screws fixation is an option for DIP joint arthrodesis. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.     

经椎板关节突螺钉固定治疗下腰椎不稳

目的探讨关节突螺钉固定在下腰椎退行性不稳定患者手术中应用的临床效果。方法对19例退行性腰椎不稳患者采用后路椎板开窗减压,椎间植骨融合,经椎板关节突螺钉固定。结果19例随访6—36个月（平均21个月）,椎间植骨融合率6个月时为86％,1年时为93％,临床症状消失,满意率92％。未出现断钉。结论采用后路椎板减压,经椎板关节突螺钉固定加椎间植骨能提高椎间融合率,使小关节稳定,解除临床症状。     

AO-wrist arthrodesis: with and without arthrodesis of the third carpometacarpal joint

The incorporation of the third carpometacarpal joint (CMCJ-3) during wrist arthrodesis is controversial. This retrospective study of 146 consecutive wrist arthrodeses with AO plate fixation specifically addresses this question. In 79 wrist arthrodeses the CMCJ-3 was also arthrodesed, and in 67 the CMCJ-3 was simply bridged. Problems relating specifically to the CMCJ-3 could not be analyzed clearly with the plate in situ. Therefore after plate removal only 81 wrists were evaluated with respect to the CMCJ-3. Of 47 wrists that had CMCJ-3 arthrodesis and plate removal, 20 developed a nonunion. Eleven of these were painful and further surgical treatment was required. In contrast, of 34 wrists with the CMCJ-3 bridged all but one remained free of symptoms after the plate had been removed. We conclude that the CMCJ-3 must not be included in the arthrodesis when performing an AO-wrist arthrodesis.     

跟骨骨折对距下关节接触特征影响的实验研究

[目的]研究载荷条件下跟骨骨折后距下关节接触特征的改变,为临床治疗提供依据。[方法]取6具包括完整足和胫腓骨远端15~20 cm的新鲜标本。剔除皮肤、肌肉和跟腱,保留除外距下关节后方及前中关节面外侧的关节囊部分,保持韧带和关节囊的完整。将压敏片插入距下关节的前中和后关节面,中立位状态下分别在500 N载荷下,对6具标本的距下关节进行加载,完成完整足的测试。然后模拟原始骨折线用微型摆动锯将跟骨后关节面分为前内和后外2块,接着按解剖复位、后外侧骨折块向跖侧移位2、5、10 mm等条件重复上述实验,记录距下关节接触特征的改变。[结果]完整距下后关节面平均受压面积为(275.67±46.02)mm2,所承载的平均应力为(1.83±0.56)MPa。跟骨后外侧骨折块向跖侧移位2 mm时,后关节面平均受压面积为(167.67±25.09)mm2,较完整跟骨受压面积显著下降(P<0.01)。后关节面所承载的应力在骨折移位2 mm时为(2.41±0.84)MPa,较完整跟骨承载应力显著增加(P<0.01)。而前中关节面的受压面积无明显改变(P>0.05)。前中关节面所受的应力仅在骨折移位10 mm时显著增加(P<0.05)。[结论]跟骨距下关节后关节面骨折移位≥2 mm即应手术复位。     

Biomechanical investigation of S2 alar-iliac screw and S1 pedicle screw fixation in the treatment of Denis type II sacral fractures

Although S2 alar-iliac screw technique has been widely used in spinal surgery, its applicability to pelvic fractures is largely unknown. This study aimed to evaluate the biomechanical stability of S2 alar-iliac screw and S1 pedicle screw fixation in the treatment of Denis II sacral fractures. Twenty-eight artificial pelvic fracture models were treated with unilateral lumbopelvic fixation, sacroiliac screw fixation, S2 alar-iliac screw and S1 pedicle screw fixation, and S2 alar-iliac screw and contralateral S1 pedicle screw fixation (Groups 1–4, respectively; N = 7 per group). Each model was cyclically tested under increasing axial compression. Optical motion-tracking was used to assess relative displacement and gap angle, and the number of failure cycles. Relative displacement was significantly smaller in Group 3 than in Groups 1 (p = 0.004) and 4 (p < 0.001) but not significantly different between Groups 3 and 2 (p = 0.290). The gap angle in Group 3 was significantly smaller than that in Group 1 (p = 0.009) on the sagittal plane but significantly larger than that in Group 4 (p = 0.006) on the horizontal plane. A number of failure cycles was significantly higher in Group 3 than in Groups 1 (p = 0.002) and 4 (p = 0.004) but not significantly different between Groups 3 and 2 (p = 0.910). From a biomechanical perspective, S2 alar-iliac screw and S1 pedicle screw fixation can provide good stability in the treatment of Denis II sacral fractures.     

Biomechanical comparison of stability of tibiotalocalcaneal arthrodesis with two different intramedullary retrograde nails

BackgroundThe aim of the study was to compare the initial construct stability of two retrograde intramedullary nail systems for tibiotalocalcaneal arthrodesis (TTCF) (A3, Small Bone Innovations; HAN, Synthes) in a biomechanical cadaver study.MethodsNine pairs of human cadaver bones were instrumented with two different retrograde nail systems. One tibia from each pair was randomized to either rod. The bone mineral density was determined via tomography to ensure the characteristics in each pair of tibiae were similar. All tests were performed in load-control. Displacements and forces were acquired by the sensors of the machine at a rate of 64 Hz. Specimens were tested in a stepwise progression starting with six times ±125N with a frequency of 1 Hz for 250 cycles each step was performed (1500 cycles). The maximum load was then increased to ±250N for another 14 steps or until specimen failure occurred (up to 3500 cycles).ResultsAverage bone mineral density was 67.4 mgHA/ccm and did not differ significantly between groups (t-test, p = .28). Under cyclic loading, the range of motion (dorsiflexion/plantarflexion) at 250N was significantly lower for the HAN-group with 7.2 ± 2.3 mm compared to the A3-group with 11.8 ± 2.9 mm (t-test, p < 0.01). Failure was registered for the HAN after 4571 ± 1134 cycles and after 2344 ± 1195 cycles for the A3 (t-test, p = .031). Bone mineral density significantly correlated with the number of cycles to failure in both groups (Spearman-Rho, r > .69, p < 0.01).ConclusionsThe high specimen age and low bone density simulates an osteoporotic bone situation. The HAN with only lateral distal bend but two calcaneal locking screws showed higher stability (higher number of cycles to failure and lower motion such as dorsiflexion/plantarflexion during cyclic loading) than the A3 with additional distal dorsal bend but only one calcaneal locking screw. Both constructs showed sufficient stability compared with earlier data from a similar test model.Clinical relevanceThe data suggest that both implants allow for sufficient primary stability for TTCF in osteoporotic and consequently also in non-osteoporotic bone.Level of evidenceNot applicable, experimental basic science study.     

Comparing biomechanical investigations about different wiring techniques of finger joint arthrodesis

Introduction Multiple operative techniques are currently used for finger arthrodesis in clinical practice. The present study was designed to compare the biomechanical characteristics of typical arthrodesis techniques used in daily practice.Material and methods Osteosynthesis techniques comprising wire cerclage, thread cerclage (PDS) or intraosseous wire suture were compared in a biomechanical experiment for resistance against bending loads. The mentioned techniques were applied to artificial specimens with resected articular surfaces or by using the cup-and-cone procedure. In this process, the specimens were tested using various Kirschner-wire insertion angles as well as different arthrodesis angles (20° vs 40°) in a 4-point bending test with each group consisting of 6 specimens of acrylic glass. The forces prevalent in the joint space were determined by prescale pressure measurement foils.Results Wire tension banding resisted significantly higher bending moments than arthrodeses with thread tension bands (p<0.05). All set-ups with tension banding techniques tolerated significantly higher loads than the intraosseous wire sutures without additional K-wires (p<0.05), which showed unfavorable dislocation of contact areas resulting in instability even under relatively minor bending loads. Using the cup-and-cone technique, a geometrically larger contact area could be achieved between two unloaded fragments, but this technique showed no advantages in the opposing bending moments compared with the conventional resection method. In both techniques, a dislocation of contact surfaces towards the palmar direction could be observed with increasing bending moment. While the use of thread tension band fixation reduces the risk of plastic deformation of both osteosynthetic material and bone stock, the problem of resorption rate has to be taken into account when choosing the material for the thread.Conclusions Considering pressure distribution and stability with and without bending loads, it is not the most rigid osteosynthesis technique which should be viewed as the ideal treatment. In contrast, it is more important to consider the various and most likely conditions to be expected in daily life after arthrodesis and therefore to chose the type of technique distributing pressure as regularly as possible.     

Experimental analysis of screw hold as judged by operators v pullout strength

An analysis of the accuracy of the operators' assessments of the hold of bone screws is reported. These assessments of screw hold were compared with measurements from pullout testing. Four operators, encompassing a range of experiences in terms of screw insertion, prepared the pilot holes, and inserted a number of screws, assigning each with a score from 0 to 10 on the basis of how good the hold was felt to be. The pullout strength for each screw was then measured using a tensometer. The results were analysed and correlation coefficients calculated. Significant correlation was observed in all four subjects, with P < 0.001 in two out of the four subjects, and 0.01 > P > 0.001 in the other two. The conclusions were that there is a strong correlation between the subjective assessment of screw hold and actual pullout strength within the four subjects analysed.     

Morphologic analysis of the subtalar joint using statistical shape modeling

Weightbearing computed tomography (WBCT) enables visualization of the foot and ankle as patients stand under load. Clinical measurements of WBCT images are generally limited to two-dimensions, which reduces the ability to quantify complex morphology of individual osseous structures as well as the alignment between two or more bones. The shape and orientation of the healthy/normal subtalar joint, in particular, is not well-understood, which makes it very difficult to diagnose subtalar pathoanatomy. Herein, we employed statistical shape modeling to evaluate three-dimensional (3D) shape variation, coverage, space, and congruency of the subtalar joint using WBCT data of 27 asymptomatic healthy individuals. The four most relevant findings were: (A) talar and calcaneal anatomical differences were found regarding the presence of (a) the talar posterior process, (b) calcaneal pitch, and (c) curvature of the calcaneal posterior facet; (B) the talar posterior facet articular surface area was significantly greater than the calcaneal posterior facet articular surface area; (C) the posterior facet varied in joint space distance, whereas the anteromedial facet was even; and (D) the posterior and anteromedial facet of the subtalar joint was consistently congruent. Despite considerable shape variation across the population, the posterior and anteromedial articular facets of the subtalar joint were consistently congruent. Results provide a detailed 3D analysis of the subtalar joint under a weightbearing condition in a healthy population which can be used for comparisons to pathological patient populations. The described SSM approach also shows promise for clinical evaluation of the subtalar joint from 3D surface reconstructions of WBCT images.     

Beware the hallucal interphalangeal joint sesamoid in first metatarsophalangeal joint arthrodesis

Background

We describe a previously unreported presentation of the hallucal interphalangeal joint sesamoid (HIPJS) following arthrodesis of the first metatarsophalangeal joint (MTP1).