Evaluation of Mid-term Outcomes Following Shoulder Hemiarthroplasty for Avascular Necrosis of the Humeral Head in Patients 40 Years and Younger.

In order to evaluate postoperative function and failure rates among younger patients undergoing hemiarthroplasty for humeral head avascular necrosis (AVN), data from patients < 40 years treated between December 2008 - January 2018 was retrospectively analyzed. Pain was assessed preoperatively and at final follow up using a visual analogue scale (VAS). The American Shoulder and Elbow Surgeons (ASES) standardized assessment, single assessment numeric evaluation (SANE) score, and patient satisfaction were assessed at final follow up, as well as surgical revision rates. In total, eight shoulders were included in the final analysis, with a follow up of 6.6 + 3.6 years. Analysis indicated a statistical improvement in VAS pain (p = 0.001), while comparison of postoperative function between surgical and non-surgical limbs did not demonstrate statistical differences in SANE or ASES averages (p > 0.05). At final follow up, 25% of patients expressed dissatisfaction; however, there were no cases of revision surgery. In conclusion, younger patients undergoing hemiarthroplasty for humeral head AVN experienced pain improvement and no revisions at short-to-mid-term follow up, but one-in-four indicated dissatisfaction. Level of evidence: IV, case series. (Journal of Surgical Orthopaedic Advances 32(2):118-121, 2023).

Use of Anatomical Landmarks in Ankle Arthroscopy to Determine Accuracy of Syndesmotic Reduction: A Cadaveric Study.

Background. The aim of this study was to determine the accuracy of ankle arthroscopy as a means for diagnosing syndesmotic reduction or malreduction and to determine anatomical landmarks for diagnosis. Methods. Six matched-pair cadavers (n = 12) with through-knee amputations were studied. Component parts of the syndesmosis and distal 10 cm of the interosseous membrane (IOM) were sectioned in each. The 12 specimens were divided into 2 groups: 6 specimens in the in-situ group fixed with suture button technique and 6 specimens in the malreduced group rigidly held with a 3.5-mm screw. Specimens were randomized to undergo diagnostic arthroscopy by 3 fellowship-trained foot and ankle orthopaedic surgeons in a blinded fashion. Surgeons were asked to determine if the syndesmosis was reduced or malreduced and provide arthroscopic measurements of their findings. Results. Of 36 arthroscopic evaluations, 34 (94%) were correctly diagnosed. Arthroscopic measurement of 3.5 mm diastasis or greater at the anterior aspect of the distal tibiofibular syndesmosis correlated with a posteriorly malreduced fibula. Arthroscopic evaluation of the Anterior inferior tibiofibular ligament (AITFL), IOM, Posterior inferior tibiofibular ligament (PITFL), lateral fibular gutter, and the tibia/fibula relationship were found to be reliable landmarks in determining syndesmotic reduction. An intraclass correlation coefficient (ICC) for interrater reliability of 1.00 was determined for each of these landmarks between 2 surgeons (P < .001). The ICCs between 2 surgeons' measurements and the computed tomography measurements were found to be 0.896 (P value < .001). Conclusions. Ankle arthroscopy is a reliable method to assess syndesmotic relationship when reduced in situ or posteriorly malreduced 10 mm. Levels of Evidence: Level V: Cadaveric.

Variations in Blood Supply From Proximal to Distal in the Ulnar Collateral Ligament of the Elbow: A Qualitative Descriptive Cadaveric Study.

BACKGROUND: The vascular supply of the ulnar collateral ligament (UCL) is unknown. Previous studies reported varying success in return-to-play rates after nonoperative management of partial UCL tears and suggested a varying healing capacity as possibly related to the location of the UCL injury. PURPOSE: To analyze the macroscopic vascular anatomy of the UCL of the elbow. STUDY DESIGN: Descriptive laboratory study. METHODS: Eighteen fresh-frozen male cadaveric elbows from 9 donors were sharply dissected 15 cm proximal to the medial epicondyle. Sixty milliliters of India ink was injected through the brachial artery of each elbow. Arms were then frozen at -10°C, radial side down, in 15° to 20° of elbow flexion. A band saw was used to section the frozen elbows into 5-mm coronal or sagittal sections. Sections were cleared for visualization with the modified Spalteholz technique. Images of the specimens were taken, and qualitative description of UCL vascularity was undertaken. RESULTS: The authors consistently found a dense blood supply to the proximal UCL, while the distal UCL was hypovascular. They also observed a possible osseous contribution to the proximal UCL from the medial epicondyle in addition to an artery from the flexor/pronator musculature that consistently appeared to provide vascularity to the proximal UCL. The degree of vascular penetration from proximal to distal in the UCL ranged from 39% to 68% of the overall UCL length, with a 49% mean length of vascular penetration of the UCL. CONCLUSION: This study found a difference in the vascular supply of the UCL. The proximal UCL was well vascularized, while the distal UCL was hypovascular. This difference in vascular supply may be a factor in the differential healing capacities of the UCL based on the location of injury. CLINICAL RELEVANCE: An improved understanding of the macroscopic vascular supply of the UCL may aid in the clinical management of partial UCL tears and suggests an indication for these treatments with respect to location of UCL injuries.

Biomechanical Comparison of 3 Novel Repair Techniques for Radial Tears of the Medial Meniscus: The 2-Tunnel Transtibial Technique, a "Hybrid" Horizontal and Vertical Mattress Suture Configuration, and a Combined "Hybrid Tunnel" Technique.

BACKGROUND: Historically, radial meniscal tears were treated with partial or near-total meniscectomy, which usually resulted in poor outcomes. Radial meniscal tears function similar to a total meniscectomy and are challenging to treat. Repair of radial meniscal tears should be performed to prevent joint deterioration and the need for salvage procedures in the future. PURPOSE/HYPOTHESIS: The purpose was to compare 3 repair techniques for radial tears of the medial meniscus: the 2-tunnel, hybrid, and hybrid tunnel techniques. It was hypothesized that there would be no differences among the 3 groups in regard to gapping and ultimate failure strength. STUDY DESIGN: Controlled laboratory study. METHODS: Thirty human male cadaver knees (10 matched pairs, n = 20; 10 unpaired, n = 10) were used to compare the 2-tunnel, hybrid, and hybrid tunnel repairs. A complete radial tear was made at the midbody of the medial meniscus. Repairs were performed according to the described techniques. Specimens were potted and mounted on a universal material testing machine where each specimen was cyclically loaded for 1000 cycles before experiencing a pull to failure. Gap distances at the tear site, ultimate failure load, and failure location were measured and recorded. RESULTS: After 1000 cycles of cyclic loading, there were no significant differences in displacement among the 2-tunnel repair (3.0 ± 1.7 mm), hybrid repair (3.0 ± 0.9 mm), and hybrid tunnel repair (2.3 ± 1.0 mm; P = .4042). On pull-to-failure testing, there were also no significant differences in ultimate failure strength among the 2-tunnel repair (259 ± 103 N), hybrid repair (349 ± 149 N), and hybrid tunnel repair (365 ± 146 N; P = .26). However, the addition of vertical mattress sutures to act as a "rip stop" significantly reduced the likelihood of the sutures pulling through the meniscus during pull-to-failure testing for the hybrid and hybrid tunnel repairs (4 of 16, 25%) as compared with the 2-tunnel repair (7 of 9, 78%; P = .017). CONCLUSION: The results showed equivalent biomechanical testing with regard to gap distance and pull-to-failure strength among the 3 repairs. The addition of the vertical mattress sutures to act as a rip stop was effective in preventing meniscal cutout through the meniscus. CLINICAL RELEVANCE: Effective healing of radial meniscal tears after repair is paramount to prevent joint deterioration and symptom development. Each tested repair showed a biomechanically equivalent and stable construct to use to repair radial meniscal tears. The authors recommend that rip stop vertical mattress sutures be used, especially in poor-quality meniscal tissue, to prevent suture cutout.

Quantitative and Qualitative Assessment of the Posterior Medial Meniscus Anatomy: Defining Meniscal Ramp Lesions.

BACKGROUND: Meniscal ramp lesions have been defined as a tear of the peripheral attachment of the posterior horn of the medial meniscus (PHMM) at the meniscocapsular junction or an injury to the meniscotibial attachment. Precise anatomic descriptions of these structures are limited in the current literature. PURPOSE: To quantitatively and qualitatively describe the PHMM and posteromedial capsule anatomy pertaining to the location of a meniscal ramp lesion with reference to surgically relevant landmarks. STUDY DESIGN: Descriptive laboratory study. METHODS: Fourteen male nonpaired fresh-frozen cadavers were used. The locations of the posteromedial meniscocapsular and meniscotibial attachments were identified. Measurements to surgically relevant landmarks were performed with a coordinate measuring system. To further analyze the posteromedial meniscocapsular and meniscotibial attachments, hematoxylin and eosin and alcian blue staining were conducted on a separate sample of 10 nonpaired specimens. RESULTS: The posterior meniscocapsular attachment had a mean ± SD length of 20.2 ± 6.0 mm and attached posteroinferiorly to the PHMM at a mean depth of 36.4% of the total posterior meniscal height. The posterior meniscotibial ligament attached on the PHMM 16.5 mm posterior and 7.7 mm medial to the center of the posterior medial meniscal root attachment. The meniscotibial ligament tibial attachment was 5.9 ± 1.3 mm inferior to the articular cartilage margin of the posterior medial tibial plateau. The posterior meniscocapsular attachment converged with the meniscotibial ligament at the most posterior point of the meniscocapsular junction in all specimens. Histological staining of the meniscocapsular and meniscotibial ligament PHMM attachments showed similar structure, cell density, and fiber directionality, with no qualitative difference in the makeup of their collagen matrices across all specimens. CONCLUSION: The anatomy of the area where a medial meniscal ramp tear occurs revealed that the 2 posterior meniscal attachments merged at a common attachment on the PHMM. Histological analysis validated a shared attachment point of the meniscocapsular and meniscotibial attachments of the PHMM. CLINICAL RELEVANCE: The findings of this study provide the anatomic foundation for an improved understanding of the meniscocapsular and meniscotibial attachments of the PHMM, which may help provide a more precise definition of a meniscal ramp lesion.

Knotless Suture Anchor Repair of Anterolateral Meniscus Root After Iatrogenic Injury.

In recent years there has been increased attention on preserving the menisci because they perform vital roles in maintaining knee joint homeostasis. The anterolateral (AL) meniscal root is particularly vulnerable during anterior cruciate ligament reconstruction. When the AL root is iatrogenically injured, it is imperative that it is repaired in a timely fashion to prevent early-onset osteoarthritis. In this article we outline our knotless suture anchor repair for AL root tears.