Anatomic and Biomechanical Study of the Forearm Interosseous Membrane, Distal Oblique Bundle, and Triangular Fibrocartilage Complex: Role in Galeazzi Fracture Dislocation.

Purpose: The purpose of this study was to measure distal radioulnar joint (DRUJ) dislocation and radioulnar displacement associated with sequential sectioning of the different bands of the interosseous membrane and triangular fibrocartilage complex in the simulation of a Galeazzi fracture dislocation. Methods: Twelve fresh-frozen cadaver forearms were dissected. We examined the anatomy and function of the forearm interosseous membrane. Each forearm was then mounted onto a biomechanical wrist and forearm device. In the control group, radial osteotomy was performed and the degree of DRUJ displacement with progressive loads was measured. In addition to radial osteotomy, in group 1, the central band (CB) was sectioned; in group 2, the CB, distal membranous portion of the interosseous membrane, and distal oblique bundle were sectioned; and in group 3, the CB, distal membranous portion of the interosseous membrane, distal oblique bundle, and triangular fibrocartilage complex were sectioned. Results: The radioulnar displacement (mm) at 25 N, 50 N, and 75 N was recorded. In group 1, applying progressive loads resulted in an average DRUJ displacement of 4.3, 5.9, and 7.9 mm, respectively. In group 2, the displacement was 5.2, 5.7, and 6.9 mm, respectively. In group 3, the displacement was 6.2, 8.1, and 9.9 mm, respectively. Our study showed a correlation between increase in the load applied to the same injury and the degree of displacement (P = .001). In group 3, the degree of DRUJ displacement was statistically increased compared to the other groups (P = .04). Conclusions: Migration of the radius under loads implies disruption of both the CB and triangular fibrocartilage complex. The distal oblique bundle by itself does not seem to have a relevant role in radioulnar displacement at the DRUJ. Clinical relevance: This study provides insights into the interosseous membrane and stability of the DRUJ, which can contribute to a better understanding of Galeazzi fracture-dislocations.

A Cadaver Based Comparison of Two Elastic Tension Proximal Interphalangeal Joint (PIPJ) Extension Orthoses with Focus on Force Generation and Pressure Distribution.

Proximal interphalangeal joint flexion contracture is a frequent condition in hand therapy. Clinicians most frequently apply orthosis management for conservative treatment. Orthoses should apply forces for long periods of time following the total end range time (TERT) concept. These forces necessarily transmit through the skin; however, skin has physiological limitations determined by blood flow. Using three fresh frozen human cadavers, this study quantified and compared forces, skin contact surfaces and pressure of two finger orthoses, an elastic tension digital neoprene orthosis (ETDNO) and an LMB 501 orthosis. The study also investigated the effects of a new method of orthosis construction (serial ETDNO orthoses) that customizes forces to a specific finger position. We evaluated forces and contact surfaces for multiple ETDNO models tailored to the cadaver fingers in multiple PIP flexion positions. The results showed that the LMB 501 orthosis applied pressures beyond the recommended limits if applied for more than eight hours a day. This fact was the cause of time limited LMB orthosis application. This results also show that, at 30° of PIPJ flexion, straight ETDNOs created a mean pressure approaching the end of the recommended pressure limits. If the therapist modified the ETDNO design, the skin pressure decreased and reduced the risk of skin damage. With the results of this study, we concluded that for PIPJ flexion contracture, the upper limit of force application is 200 g (1.96 N). Forces beyond this amount would likely cause skin irritation and possibly skin injuries. This would cause a reduction in the daily TERT and limit outcomes.

A Comparison between Two Intervals of Daily Total End Range Time for Treatment of Proximal Interphalangeal Joint Flexion Contracture Using an Elastic Tension Digital Neoprene Orthosis.

Focusing on fingers with proximal interphalangeal joint flexion contractures, this study seeks to determine whether significant differences exist between the joint passive range of motion PROM improvement when receiving higher doses of daily total end range time (TERT) compared to those that receive lower doses. The study randomized a parallel group of fifty-seven fingers in fifty patients with concealed allocation and assessor blinding. Divided into two groups receiving different doses of daily total end range time with an elastic tension digital neoprene orthosis, they also participated in an identical exercise program. Patients reported orthosis wear time, and the researchers performed goniometric measurements at every session during the three-week period. The primary outcome related the time patients wore the orthosis to the degrees of improvement in PROM extension. Compared to group B (daily TERT of twelve hours), group A (TERT, twenty+ hours) showed a statistically significant greater improvement in PROM after three weeks of treatment. Group A improved by a mean of 29° compared to group B's mean of 19° improvement. This study provides evidence that a higher dose of daily TERT can generate better results in the treatment of the proximal interphalangeal joint flexion contractures.

Biomechanical comparison of anterolateral ligament anatomical reconstruction with a semi-anatomical lateral extra-articular tenodesis. A cadaveric study.

BACKGROUND: To compare the biomechanical behavior of an anterolateral ligament (ALL) anatomical reconstruction and a semianatomical lateral extra-articular tenodesis (LET) in the context of an anterior cruciate ligament (ACL) reconstruction combined with an anterolateral lesion. METHODS: Twelve cadaveric knees were studied using a testing machine to assess the internal tibial rotation and anterior tibial translation across six surgical states: intact knee, ACL lesion, ACL + ALL lesion, ACL isolated reconstruction, ACL + ALL anatomical reconstruction and ACL + LET procedure. ALL and LET grafts were fixed at full knee extension and neutral rotation. RESULTS: Presented with combined ACL and ALL lesions, isolated ACL reconstruction failed to restore the internal tibial rotation to intact-knee values (P > 0.05 for all angles). The addition of both an ALL reconstruction and LET procedure significantly reduced the internal rotation, restoring the rotation laxity to intact-knee values at 0° and 30° of flexion (P < 0.05) and with a certain level of overconstraint at 60° and 90° (mean 3°â€¯±â€¯2SD). A higher tendency to overconstraint was observed with the LET, but there was no significant difference when comparing the ALL reconstruction with the LET (P > 0.05 for all angles). CONCLUSIONS: Residual rotational laxity was found after isolated ACL reconstruction in the presence of an anterolateral lesion. The combination of ACL reconstruction with anatomical ALL reconstruction or the LET procedure resulted in restoration to intact-knee values but with a certain degree of overconstraint in higher flexion angles. Both techniques showed optimal biomechanical results with no data supporting the advantage of one over the other.

Safe drilling angles avoid femoral tunnel complications during combined anterolateral ligament and anterior cruciate ligament reconstruction.

PURPOSE: To determine the best angle to drill the femoral tunnels of an anterolateral ligament (ALL) anatomic reconstruction combined with a single-bundle anterior cruciate ligament (ACL) reconstruction to avoid tunnel collisions and cortical disruption. METHODS: Ten cadaveric knees were studied. Single-bundle anatomic ACL femoral tunnels were arthroscopically drilled. The starting point of the ALL femoral tunnel was located posterior and superior to the lateral epicondyle. ALL tunnels were drilled at four different angulations: (1) 0° axial/0° coronal, (2) 0° axial/30° coronal superior, (3) 30° axial anterior/0° coronal, and (4) 30° axial anterior 30° coronal superior. Specimens were scanned by computed tomography to measure the relations of each trajectory with the ACL socket and the nearest cortical bone. RESULTS: None of the four trajectories studied presented risk of collision with the ACL. The tunnel at 30° anterior/30° proximal presented the safest distance to the ACL socket (P = 0.01) [mean distance 18.6 mm (SD ± 6.7)]. However, both tunnels angled at 0° in the axial plane presented a high risk of posterior femoral cortex disruption (P = 0.01), either by close proximity or direct contact in some specimens (mean distance 3.1 mm (SD ± 2.8) at 0° axial/0° coronal and 3.7 mm (SD ± 2.2) at 0° axial/30° coronal). CONCLUSIONS: When performing simultaneous ACL and ALL ligament reconstruction, the ALL femoral tunnel should be drilled with an angle of 30° anterior in the axial plane and 30° proximal in the coronal plane. Tunnels with an angle of 0° in the axial plane showed high risk of contact and disruption of the posterior femoral cortex; thus, these angles should be avoided. The clinical relevance of this work is that an ALL anatomical reconstruction does not represent a risk when performing a simultaneous ACL reconstruction as long as the ALL tunnel is reamed with a proximal and anterior angulation.

Hemodynamic Instability after Low-Energy Thigh Contusion Caused by Injury to the Femoral Artery: A Case Report and Literature Review.

Acute vascular injuries have been described in relation to high-energy trauma accidents or in patients undergoing surgery in the femoral area. We describe a healthy patient who sustained a direct, low-energy contusion in the thigh and presented haemodynamic instability. Arteriography was used to locate the point of bleeding, and embolisation and vessel occlusion were carried out to stop the haemorrhage. The genetic study identified the COL3A1 gene mutation; accordingly, the patient was diagnosed with the Ehlers-Danlos syndrome type IV (vascular type).

New surgical approach to advanced Kienböck disease: lunate replacement with pedicled vascularized scaphoid graft and radioscaphoidal partial arthrodesis.

Reconstructive procedures such as proximal row carpectomy or partial arthrodesis have been commonly proposed for advanced Kienböck disease (Lichtmann IIIB to IV). The purpose of this study is to evaluate an alternative surgical technique to advanced Kienböck disease: lunate excision and replacement with pedicled vascularized scaphoid graft and partial radioscaphoidal arthrodesis. The main advantage of the proposed intervention is to preserve mobility while not jeopardizing prime clinical outcomes such as pain. By replacing the devitalized lunate we aim at maintaining midcarpal range of motion, and preventing disease progression with carpal collapse and osteoarthritis of the wrist. Between 2002 and 2008, 13 patients of mean age 41 years (range, 25 to 57 y) were operated using this technique. The surgical act included 3 key steps. First, we excised the lunate, then, filled the generated gap with the rotated scaphoid, using it as a pedicled vascularized autograft. Finally, we performed a partial radioscaphoid arthrodesis. At the final follow-up, none of the intervened patients had pain at rest, and 6 patients could perform nonrestricted daily activities. The average postoperative range of motion in flexion/extension was 70 degrees (range, 55 to 90 degrees), 44% (range, 38% to 54%) of what could be achieved by the contralateral arm, and only 16% (range, 14% to 19%) or 25 degrees (range, 18 to 30 degrees) less than the preoperative range of motion of the same wrist. Grip strength improved by more than 30% (range, 24% to 36%). At an average follow-up of 4 years after surgery, 12 of 13 patients had no radiographic evidence of osteoarthritis or collapse of subchondral bone at the level of the new scaphocapitate joint. At follow-up evaluation, the average DASH score was 14 points (range, 6 to 20). The patients experienced a significant improvement in their functional abilities, achieving good results compared with the conventional techniques. The absence of carpal collapse and good functional results are encouraging.

Dissection of intercostal nerves by means of assisted video thoracoscopy: experimental study.

In total brachial plexus preganglionic lesions (C5-C6-C7-C8 and T1) different extraplexual neurotizations are indicated for partial motor function restitution. Mostly for the flexion of the elbow. Neurotization with intercostal nerves (ICN) to musculocutaneous nerve has been known and accepted during many years with different results 2 - 5. The customary technique as described by various authors is carried out by means of a large submammary incision to harvest three or four intercostal nerves (Figure 1). Then are connected by direct suture or grafts to the musculocutaneous nerve or its motor branches 6 - 7. In this article the authors described the possibility of dissection intercostal nerves by means of assisted video thoracoscopy. (VATS-videdo assisted thoracic surgery).

The effect of the dorsal intercarpal ligament on lunate extension after distal scaphoid excision.

PURPOSE: After a distal scaphoid excision, most wrists develop a mild form of carpal instability-nondissociative with dorsal intercalated segment instability. Substantial dysfunctional malalignment is only occasionally seen. We hypothesized that distal scaphoid excision would lead to carpal instability-nondissociative with dorsal intercalated segment instability in cadavers and that the dorsal intercarpal (DIC) ligament plays a role in preventing such complications. METHODS: We used 10 cadaver upper extremities in this experiment. A customized jig was used to load the wrist with 98 N. Motion of the capitate and lunate was monitored using the Fastrak motion tracking system. Five specimens had a distal scaphoid excision first, followed by excision of the DIC ligament, whereas the other 5 specimens first had excision of the DIC ligament and then had a distal scaphoid excision. Rotation of the lunate and capitate was calculated as a sum of the relative motions between each intervention and was compared with its original location before intervention (control) for statistical analysis. RESULTS: Distal scaphoid excision and subsequent DIC ligament excision both led to significant lunate extension. DIC ligament excision alone resulted in lunate flexion that was not statistically significant. After DIC ligament excision, distal scaphoid excision led to significant lunate extension. Capitate rotation was minimal in both groups, verifying that the overall wrist position did not change with loading. CONCLUSIONS: Distal scaphoid excision leads to significant lunate extension through an imbalance in the force couple between the scaphotrapeziotrapezoidal joint and the triquetrum-hamate joint. The DIC ligament may serve as a secondary stabilizer to the lunocapitate joint and prevent further lunate extension with the wrist in neutral position. CLINICAL RELEVANCE: The development of a clinically symptomatic carpal instability-nondissociative with dorsal intercalated segment instability with lunocapitate subluxation after distal scaphoid excision may be due to an incompetent DIC ligament.

How to avoid injuries of the superior gluteal nerve.

BACKGROUND: Injuries to the superior gluteal nerve are a common complication in hip replacement surgery. They can be avoided with a good anatomical knowledge of the course of the superior gluteal nerve. METHODS: We dissected 29 half pelvises of adult cadavers. The distance and the angle from the entry points of branches of the superior gluteal nerve into the deep surface of the gluteus medium and minimus muscles to the midpoint of the superior border of the greater trochanter were measured. RESULTS: The dissections revealed that the nerve divided into 2 branches (86.20%) or 3 branches (13.8%). The more caudal branch was responsible for innervation of the tensor fascia latae. CONCLUSIONS: A 2-3-cm safe area above the greater trochanter is appropriate to prevent nerve damage.

Ultrasound-anatomic correlation of the peripheral nerves of the upper limb.

BACKGROUND: Sonography allows good visualization of the peripheral nerves and the vascular and muscular structures that surround them. Our goals are to provide an easy-to-use atlas that gives accurate information about the locations and relations among the nerves in the different parts of the arm and to correlate it with the probe position and the ultrasound images. MATERIALS AND METHODS: A cadaver right arm was used for the present study. The arterial and venous vessels were injected with red and blue-colored latex to obtain a better correlation with ultrasound slices from two healthy volunteers. The specimen was frozen and then cut into slices with an average thickness of 2 cm, starting from the lower part of the axilla. RESULTS: Close correlation was present between the ultrasound and anatomic slices identifying the main muscular, vascular and nervous structures. In the arm, median, ulnar and radial nerves were easily seen because of the proximity to vascular landmark and their size. In the forearm, the ulnar nerve was also easy to identify because of the factors previously mentioned; the median nerve was easy to locate between the flexor digitorum superficialis and profundus muscles. The superficial branch of the radial arm was seen in most cases, although some skill was required. CONCLUSION: Ultrasound is a useful tool to identify the main nerves of the upper arm. This atlas indicates the locations and relations among the nerves, correlating with the ultrasound appearance.

Intraosseous vascularity of the distal radius: anatomy and clinical implications in distal radius fractures.

This study aimed to describe the intraosseous blood supply of the distal radius and its clinical implications in distal radius fractures. Twelve adult wrists from fresh cadavers (six males, six females, 50-90 years of age, mean 68 years) were injected through the brachial artery with latex. Dissections were performed using magnifying loupes and hands were processed using the Spalteholz technique. The distal radius was supplied by three main vascular systems: epiphyseal, metaphyseal, and diaphyseal. The palmar epiphyseal vessels branched from the radial artery, palmar carpal arch, and anterior branch of the anterior interosseous artery. These vessels entered the bone through the radial styloid process at level of the Lister's tubercle but palmar and sigmoid notch. The dorsal contribution to Lister's tubercle is to the dorsal epiphyseal vessels. The intraosseous point of entry to the dorsal epiphyseal vessels was from the fourth and fifth extensor compartment arteries. In the metaphyseal area, we found numerous periosteal and cortical branches originating deep in the pronator quadratus and the anterior interosseous artery. These branches provided the main supply to the distal radius. Vessels perforated the bone and formed an anastomotic network. In the diaphyseal area, only the nutrient vessel provided intraosseous vascularity in the distal radius. Numerous metaphyseal-epiphyseal branches arise within the pronator quadratus and the anterior interosseous artery and course towards the distal radius. These branches may be fundamental to the healing of the distal radius fractures and make nonunion a rare complication.

Arteries of the scrotum: a microvascular study and its application to urethral reconstruction with scrotal flaps.

OBJECTIVE: To study scrotal microvascularization and apply the findings to the design of reliable skin flaps for reconstructive surgery of complex urethral or panurethral stenoses. MATERIALS AND METHODS: In 15 cryopreserved male cadavers, scrotal skin vascularization was explored using macro- and microdissections, and the scrotal sac made transparent using the Spalteholtz method. A meticulous descriptive analysis of the arterial network was conducted out in all cases to evaluate the number, distribution and anastomosis of the cutaneous arteries of the scrotum. RESULTS: Scrotal skin is irrigated by two main vascular systems, through the inferior external pudendal arteries and the perineal arteries, which branch into multiple scrotal arteries. These arteries are distributed in three cutaneous territories, two lateral and one central, which are widely inter-anastomosed. Each lateral territory receives an inferior external pudendal artery which accesses at the midpoint of the scrotal root and fans out to cover the entire corresponding hemiscrotum. The central cutaneous territory is vascularized through the branches of two main scrotal arteries which are a continuation of the perineal arteries and which access via the posterior face, running deeply on both sides of the septum. CONCLUSIONS: The special anatomical distribution of scrotal branches stemming from perineal arteries enables the construction of adequate reliable longitudinal median island scrotal flaps for the reconstructive surgery of panurethral stenosis, as profuse axial vascularization is ensured.

Surgical approach to the triangular fibrocartilage complex.

There are few descriptions of the surgical exposure of the ulnar aspect of the wrist. The anatomy of the dorsoulnar aspect of the wrist was explored in 7 cadaver wrists with special attention to developing a surgical approach to the dorsum of the radio-ulno-carpal joint. Using the experience from previous authors and the knowledge gained from our cadaveric dissections, a surgical approach was designed that provides wide exposure of the dorsoulnar aspect of the wrist. The anatomic layers are dissected in a distinct pattern that allows preservation of the extensor carpi ulnaris and its sheath as well as a strong closure of each layer and restoration of the anatomy. Minimal postoperative immobilization is required, and rehabilitation can be started as early as 2 weeks postoperatively. This approach provides access to the distal radioulnar joint, triangular fibrocartilage complex, distal ulna, and lunotriquetral joint, thus allowing multiple possible procedures through a single, universal approach.