Does the Suprascapular Nerve Move within the Suprascapular Notch?Biomechanical Perspective Using the Finite Element Method

Purpose@#We aimed to analyze changes in suprascapular nerve (SSN) position within the suprascapular notch during in vivo shoulder abduction. @*Materials and Methods@#Three-dimensional models of the shoulder complex were constructed based on magnetic resonance imaging of the brachial plexus (BP-MR) in a patient diagnosed with SSN dysfunction but normal scapular movement. Using BP-MR in neutral position and computed tomography data on shoulder abduction, shoulder abduction was simulated as the transition between two positions of the shoulder complex with overlapping of a neutral and abducted scapula. SSN movement during abduction was evaluated using the finite element method. Contact stress on the SSN was measured in the presence and absence of the transverse scapular ligament (TSL). @*Results@#In the neutral position, the SSN ran almost parallel to the front of the TSL until entering the suprascapular notch and slightly contacted the anterior-inferior border of the TSL. As shoulder abduction progressed, contact stress decreased due to gradual loss of contact with the TSL. In the TSL-free scapula, there was no contact stress on the SSN in the neutral position. Towards the end of shoulder abduction, contact stress increased again as the SSN began to contact the base of the suprascapular notch in both TSL conditions. @*Conclusion@#We identified changes in the position of the SSN path within the suprascapular notch during shoulder abduction. The SSN starts in contact with the TSL and moves toward the base of the suprascapular notch with secondary contact. These findings may provide rationale for TSL release in SSN entrapment.

Effect of co-administration of atelocollagen and hyaluronic acid on rotator cuff healing

Background@#This study aimed to evaluate the co-administration effect of atelocollagen combined with hyaluronic acid (HA) injections fortreatment of full-thickness rotator cuff tear (RCT). @*Methods@#Eighty patients who underwent arthroscopic rotator cuff repair for full-thickness RCT from March 2018 to November 2019 wereenrolled. The patients were randomly allocated to the following groups: combined atelocollagen and HA injection (group I, n=28), only HAinjection (group II, n=26), and no injection (group III, n=26). Clinical outcomes were assessed at 3, 6, and 12 months after surgery usingthe American Shoulder and Elbow Surgeons score, visual analog scale pain score, functional scores (pain visual analog scale, function visualanalog score), and range of motion. Magnetic resonance imaging was performed 12 months after surgery to evaluate rotator cuff integrity. @*Results@#Preoperative demographic data and postoperative clinical outcomes did not differ significantly among the three groups (p>0.05).However, in group I, the number of steroid injections after surgery was significantly lower than that in the other groups (p=0.011). The retear rate on follow-up magnetic resonance imaging was significantly higher in group II (9.5%, n=2) and group III (13.6%, n=3) than ingroup I (0%, p=0.021). @*Conclusions@#Co-administration of atelocollagen and HA improves healing of the rotator cuff and increases the integrity of the rotator cuffrepair site. This study provides encouraging evidence for use of combined atelocollagen-HA injections to treat patients with full-thicknessRCT.

Effect of co-administration of atelocollagen and hyaluronic acid on rotator cuff healing

Background@#This study aimed to evaluate the co-administration effect of atelocollagen combined with hyaluronic acid (HA) injections fortreatment of full-thickness rotator cuff tear (RCT). @*Methods@#Eighty patients who underwent arthroscopic rotator cuff repair for full-thickness RCT from March 2018 to November 2019 wereenrolled. The patients were randomly allocated to the following groups: combined atelocollagen and HA injection (group I, n=28), only HAinjection (group II, n=26), and no injection (group III, n=26). Clinical outcomes were assessed at 3, 6, and 12 months after surgery usingthe American Shoulder and Elbow Surgeons score, visual analog scale pain score, functional scores (pain visual analog scale, function visualanalog score), and range of motion. Magnetic resonance imaging was performed 12 months after surgery to evaluate rotator cuff integrity. @*Results@#Preoperative demographic data and postoperative clinical outcomes did not differ significantly among the three groups (p>0.05).However, in group I, the number of steroid injections after surgery was significantly lower than that in the other groups (p=0.011). The retear rate on follow-up magnetic resonance imaging was significantly higher in group II (9.5%, n=2) and group III (13.6%, n=3) than ingroup I (0%, p=0.021). @*Conclusions@#Co-administration of atelocollagen and HA improves healing of the rotator cuff and increases the integrity of the rotator cuffrepair site. This study provides encouraging evidence for use of combined atelocollagen-HA injections to treat patients with full-thicknessRCT.

Treatment of acute high-grade acromioclavicular joint dislocation

Acromioclavicular (AC) joint dislocations account for about 9% of shoulder injuries. Among them, acute high-grade injury following high-energy trauma accounts for a large proportion of patients requiring surgical treatment. However, there is no gold standard procedure for operative treatment of acute high-grade AC joint injury, and several different procedures have been used for this purpose in clinical practice. This review article summarizes the most recent and relevant surgical options for acute high-grade AC joint dislocation patients and the outcomes of each treatment type.

Evaluation of Muscular Atrophy and Fatty Infiltration Using Time-zero Magnetic Resonance Imaging as Baseline Data, After Rotator Cuff Repair

BACKGROUND: This study evaluated postoperative changes in the supraspinatus from time-zero to 6 months, using magnetic resonance imaging (MRI). We hypothesized that restoration of the musculotendinous unit of the rotator cuff by tendon repair immediately improves the rotator cuff muscle status, and maintains it months after surgery. METHODS: Totally, 76 patients (29 men, 47 women) with rotator cuff tears involving the supraspinatus tendon who underwent arthroscopic rotator cuff repairs were examined. MRI evaluation showed complete repair with intact integrity of the torn tendon at both time-zero and at 6 months follow-up. All patients underwent standardized MRI at our institution preoperatively, at 1 or 2 days postoperative, and at 6 months after surgery. Supraspinatus muscular (SSP) atrophy (Thomazeau grade) and fatty infiltrations (Goutallier stage) were evaluated by MRI. The cross-sectional area of SSP in the fossa was also measured. RESULTS: As determined by MRI, the cross-sectional area of SSP significantly decreased 11.41% from time-zero (immediate repair) to 6 months post-surgery, whereas the Goutallier stage and Thomazeau grade showed no significant changes (p<0.01). Furthermore, compared to the preoperative MRI, the postoperative MRI at 6 months showed a no statistically significant increase of 8.03% in the cross-sectional area. In addition, morphological improvements were observed in patients with high grade Goutallier and Thomazeau at time-zero, whereas morphology of patients with low grade factors were almost similar to before surgery. CONCLUSIONS: Our results indicate that cross-sectional area of the initial repair appears to decrease after a few months postoperatively, possibly due to medial retraction or strained muscle.

Evaluation of Muscular Atrophy and Fatty Infiltration Using Time-zero Magnetic Resonance Imaging as Baseline Data, After Rotator Cuff Repair

BACKGROUND@#This study evaluated postoperative changes in the supraspinatus from time-zero to 6 months, using magnetic resonance imaging (MRI). We hypothesized that restoration of the musculotendinous unit of the rotator cuff by tendon repair immediately improves the rotator cuff muscle status, and maintains it months after surgery.@*METHODS@#Totally, 76 patients (29 men, 47 women) with rotator cuff tears involving the supraspinatus tendon who underwent arthroscopic rotator cuff repairs were examined. MRI evaluation showed complete repair with intact integrity of the torn tendon at both time-zero and at 6 months follow-up. All patients underwent standardized MRI at our institution preoperatively, at 1 or 2 days postoperative, and at 6 months after surgery. Supraspinatus muscular (SSP) atrophy (Thomazeau grade) and fatty infiltrations (Goutallier stage) were evaluated by MRI. The cross-sectional area of SSP in the fossa was also measured.@*RESULTS@#As determined by MRI, the cross-sectional area of SSP significantly decreased 11.41% from time-zero (immediate repair) to 6 months post-surgery, whereas the Goutallier stage and Thomazeau grade showed no significant changes (p<0.01). Furthermore, compared to the preoperative MRI, the postoperative MRI at 6 months showed a no statistically significant increase of 8.03% in the cross-sectional area. In addition, morphological improvements were observed in patients with high grade Goutallier and Thomazeau at time-zero, whereas morphology of patients with low grade factors were almost similar to before surgery.@*CONCLUSIONS@#Our results indicate that cross-sectional area of the initial repair appears to decrease after a few months postoperatively, possibly due to medial retraction or strained muscle.

Needling Procedures for Calcific Tendinitis Performed by Orthopedic Surgeons

BACKGROUND: Common and effective treatments for calcific tendinitis involve needling procedures. However, it has been widespread practice to refer patients with calcific tendinitis, which is a predominantly orthopedic condition, to radiology department. The purpose of this study was to compare clinical and radiological outcomes after ultrasound-guided needling for calcific tendinitis between the orthopedics and radiology department. METHODS: Seventy-seven shoulders (Group 1) and 38 shoulders (Group 2) treated in the radiology and orthopedic department, respectively. A fellowship-trained orthopedic surgeon and a musculoskeletal radiologist each performed the procedure of ultrasound-guided needle decompression with subacromial steroid injection. Clinical outcomes was evaluated using the visual analogue scale for pain (pVAS) and the American Shoulder and Elbow Surgeons (ASES) shoulder score before treatment and at each follow-up. The pre- and post-needling size and shape of the calcific deposits were compared between the two groups. RESULTS: We analyzed a total of 56 shoulders for Group 1 and 32 shoulders for Group 2. The mean age and sex ratio of the patients no significantly different. We found that the mean decrease in the diameter of calcification between pre- and post-needling was 9.0 mm for Group 1 and 13.1 mm for Group 2; the difference was significantly larger in Group 2 than in Group 1. Both groups showed improved pVAS and ASES scores after needling but the extent of these improvements did not differ with the type of operator. CONCLUSIONS: Needling decompression performed by orthopedic surgeons could a viable option for the treatment of calcific tendinitis.

Effectiveness of the Anti-adhesive Agent Protescal after Arthroscopic Rotator Cuff Repair: A Retrospective Study

BACKGROUND: Many hyaluronic acid (HA)-based anti-adhesive agents have been commercialized for clinical use in the pharmaceutical market. But their efficacy in arthroscopic rotator cuff repairs remains elusive. To determine their efficacy, we performed a comparative analysis of the effects of two hyaluronate/carboxymethylcellulose (CMC)-based anti-adhesive agents, Protescal and Guardix. METHODS: We recruited a total of 256 patients who had received an arthroscopic rotator cuff repair at our hospital between January 2014 and March 2015. Among them, 96 patients fulfilled the study's selection criteria and were enrolled as the final population sample. Thirty patients who had received a postoperative injection of Protescal were allocated into Group A. Another 30 patients who had received a postoperative injection of Guardix were allocated into Group B. As controls, 36 patients who did not receive any injection were allocated into Group C. The patients included in this study were aged between 19 and 75 years. For the clinical assessment, we measured the following clinical parameters—the visual analogue scale for pain (PVAS), the American Shoulder and Elbow Surgeons (ASES) score, and the constant score, as well as passive range of motions (ROMs)—at three time-points (preoperatively, 2-month postoperatively, and 6-month postoperatively). RESULTS: We found that Group A compared to Group B tended to show a swifter recovery in passive anterior elevation and in internal rotation by the 2-month postoperative follow-up, but the differences were not statistically significant. CONCLUSIONS: We found that the effects of HA/CMC-based injections were minimal after arthroscopic rotator cuff repairs.

Needling Procedures for Calcific Tendinitis Performed by Orthopedic Surgeons

BACKGROUND: Common and effective treatments for calcific tendinitis involve needling procedures. However, it has been widespread practice to refer patients with calcific tendinitis, which is a predominantly orthopedic condition, to radiology department. The purpose of this study was to compare clinical and radiological outcomes after ultrasound-guided needling for calcific tendinitis between the orthopedics and radiology department. METHODS: Seventy-seven shoulders (Group 1) and 38 shoulders (Group 2) treated in the radiology and orthopedic department, respectively. A fellowship-trained orthopedic surgeon and a musculoskeletal radiologist each performed the procedure of ultrasound-guided needle decompression with subacromial steroid injection. Clinical outcomes was evaluated using the visual analogue scale for pain (pVAS) and the American Shoulder and Elbow Surgeons (ASES) shoulder score before treatment and at each follow-up. The pre- and post-needling size and shape of the calcific deposits were compared between the two groups. RESULTS: We analyzed a total of 56 shoulders for Group 1 and 32 shoulders for Group 2. The mean age and sex ratio of the patients no significantly different. We found that the mean decrease in the diameter of calcification between pre- and post-needling was 9.0 mm for Group 1 and 13.1 mm for Group 2; the difference was significantly larger in Group 2 than in Group 1. Both groups showed improved pVAS and ASES scores after needling but the extent of these improvements did not differ with the type of operator. CONCLUSIONS: Needling decompression performed by orthopedic surgeons could a viable option for the treatment of calcific tendinitis.

Effectiveness of the Anti-adhesive Agent Protescal after Arthroscopic Rotator Cuff Repair: A Retrospective Study

BACKGROUND: Many hyaluronic acid (HA)-based anti-adhesive agents have been commercialized for clinical use in the pharmaceutical market. But their efficacy in arthroscopic rotator cuff repairs remains elusive. To determine their efficacy, we performed a comparative analysis of the effects of two hyaluronate/carboxymethylcellulose (CMC)-based anti-adhesive agents, Protescal and Guardix. METHODS: We recruited a total of 256 patients who had received an arthroscopic rotator cuff repair at our hospital between January 2014 and March 2015. Among them, 96 patients fulfilled the study's selection criteria and were enrolled as the final population sample. Thirty patients who had received a postoperative injection of Protescal were allocated into Group A. Another 30 patients who had received a postoperative injection of Guardix were allocated into Group B. As controls, 36 patients who did not receive any injection were allocated into Group C. The patients included in this study were aged between 19 and 75 years. For the clinical assessment, we measured the following clinical parameters—the visual analogue scale for pain (PVAS), the American Shoulder and Elbow Surgeons (ASES) score, and the constant score, as well as passive range of motions (ROMs)—at three time-points (preoperatively, 2-month postoperatively, and 6-month postoperatively). RESULTS: We found that Group A compared to Group B tended to show a swifter recovery in passive anterior elevation and in internal rotation by the 2-month postoperative follow-up, but the differences were not statistically significant. CONCLUSIONS: We found that the effects of HA/CMC-based injections were minimal after arthroscopic rotator cuff repairs.

Clavicle Nonunion: Matchstick Bone-grafting and Osteosynthesis

BACKGROUND: This study was conducted to evaluate the surgical outcomes of plate fixation using autologous iliac bone graft shaped in the form of a matchstick in clavicle nonunion resulting from prior surgical or non-surgical management. METHODS: From May 2005 to February 2013, 17 patients underwent surgery for clavicle nonunion. The mean age at the time of surgery was 48.8 years. The iliac bone was harvested and shaped into slivers approximately 3 cm long, which resembled matchsticks. After opening of the medullary canal, the plate and screws were applied and cancellous bone was placed at the nonunion site. Matchstick bone grafts which were longitudinally placed and encircled on the nonunion site were tied with periosteum using 3–4 stitches. Union was determined via postoperative plane X-ray. Clinical status was evaluated using the visual analogue scale score for pain, and Constant and American Shoulder Elbow Surgeon score. RESULTS: All patients had a stable radiological union at the follow-up. The mean duration from index operation to nonunion operation was 13.2 months (7–32 months). The mean follow-up period was 20.1 months (8–56 months), and the mean duration until union was 11.2 weeks (8–16 weeks). All clinical scores were improved at the final follow-up (p<0.001). The mean segmental defect was 3.3 ± 2.6 mm (1–18 mm); and the difference in clavicular length between operative and non-operative site was 5.9 ± 6.9 mm. CONCLUSIONS: Matchstick shaped autologous iliac bone grafting technique in clavicle nonunion is acceptable with a high union rate.

Clavicle Nonunion: Matchstick Bone-grafting and Osteosynthesis

BACKGROUND: This study was conducted to evaluate the surgical outcomes of plate fixation using autologous iliac bone graft shaped in the form of a matchstick in clavicle nonunion resulting from prior surgical or non-surgical management. METHODS: From May 2005 to February 2013, 17 patients underwent surgery for clavicle nonunion. The mean age at the time of surgery was 48.8 years. The iliac bone was harvested and shaped into slivers approximately 3 cm long, which resembled matchsticks. After opening of the medullary canal, the plate and screws were applied and cancellous bone was placed at the nonunion site. Matchstick bone grafts which were longitudinally placed and encircled on the nonunion site were tied with periosteum using 3–4 stitches. Union was determined via postoperative plane X-ray. Clinical status was evaluated using the visual analogue scale score for pain, and Constant and American Shoulder Elbow Surgeon score. RESULTS: All patients had a stable radiological union at the follow-up. The mean duration from index operation to nonunion operation was 13.2 months (7–32 months). The mean follow-up period was 20.1 months (8–56 months), and the mean duration until union was 11.2 weeks (8–16 weeks). All clinical scores were improved at the final follow-up (p<0.001). The mean segmental defect was 3.3 ± 2.6 mm (1–18 mm); and the difference in clavicular length between operative and non-operative site was 5.9 ± 6.9 mm. CONCLUSIONS: Matchstick shaped autologous iliac bone grafting technique in clavicle nonunion is acceptable with a high union rate.