Comparison of patient reported outcomes following clavicle operative fixation using supraclavicular nerve sparing and supraclavicular nerve sacrificing techniques- A cohort study

Ultrasonographic visualization of anatomical variations of the supraclavicular nerves

Typical anatomy of the supraclavicular nerve (SCN) is described as originating from the cervical plexus and dividing into medial, intermediate, and lateral branches. The SCN is vulnerable to injury during clavicular surgery, leading to altered sensation post-operatively. There is also increasing interest in anesthetizing the SCN in shoulder or clavicular surgery. Utilizing a high-frequency (20 MHz) ultrasound probe, 20 healthy volunteers were scanned, giving data for 40 SCNs. For each nerve, anatomical course and branches were graphically plotted using a custom Python 3.8.12 program and Microsoft Excel. Of 40 nerves, only 19 (47.5%) demonstrated a typical course, with the rest showing considerable variability of branching patterns. Crossing branches (CBs) were found in 24 (60%) with a total of 54. Just over half (29, 54.7%) of these crossed the clavicle lateral to its midpoint, with 32 (59.6%) CBs having a diameter of ≥25% compared to that of the SCN main trunk. The distance from the mid-clavicular point at which the branches crossed the clavicle was recorded. This study demonstrated that over half the SCNs had atypical branching patterns with intra-volunteer variability. Preoperative mapping may be useful in preventing injury and subsequent numbness.

Minimally Invasive Plate Osteosynthesis with Mini-Open Technique and Supraclavicular Nerve Preservation Reduces Postoperative Numbness in Acute Displaced Midshaft Clavicle Fracture

Background: Minimally invasive plate osteosynthesis (MIPO) for clavicular shaft fracture yields favorable functional outcomes and results in less surgery-related soft tissue injury than other techniques. Anterior chest and shoulder skin numbness, a common complication after open reduction and plate fixation, is related to injury to the supraclavicular nerves. We propose MIPO combined with a mini-open approach without fluoroscopy for nerve preservation to minimize the risk of postoperative numbness compared with traditional open plating without nerve preservation. Methods: A total of 59 patients were retrospectively identified, with a follow-up period of 6 months. Thirty-two patients underwent MIPO with mini-open and nerve preservation technique (MIPO group), and 27 patients underwent traditional open plating without nerve preservation (open group). Constant-Murley shoulder outcome score, operation time, wound length, skin numbness, and number of implant removals were compared between the groups. Results: The MIPO group had significantly lower rates of anterior chest and shoulder skin numbness than the open group (MIPO: 12.5% vs. open: 55.6%; p < 0.001). Operation time was significantly longer in the MIPO group than in the open group (MIPO: 109.38 ± 18.83 vs. open: 81.48 ± 18.85; p < 0.001). Wound length was significantly shorter in the MIPO group than in the open group (MIPO: 4.73 ± 0.79 vs. open: 9.76 ± 1.64; p < 0.001). Both groups had similarly excellent Constant-Murley shoulder scores. There were significantly fewer implant removals in the MIPO group than in the open group (MIPO: 6.3% vs. open: 25.9%; p = 0.036). Neither group experienced any infection, implant failure, or nonunion. Conclusions: Our technique combining MIPO with the mini-open approach and supraclavicular nerve preservation yields a lower incidence of skin numbness than traditional open plating without nerve preservation.

Supraclavicular nerve sparing versus sacrifice during open reduction internal fixation of acute midshaft clavicle fracture

BACKGROUND

The branches of the supraclavicular nerve are often sacrificed during open reduction and internal fixation (ORIF) for clavicle fracture. No consensus exists on whether the supraclavicular nerve should be routinely identified and protected during ORIF.

METHODS

We developed a simple method to make nerve sparing easier; Wide-Awake Local Anesthesia No Tourniquet (WALANT) solution is locally injected prior to the surgical incision being made. This retrospective study enrolled 340 patients and divided them into supraclavicular-nerve-sparing (n = 45) and supraclavicular-nerve-sacrifice (n = 295) groups. Surgical outcomes-including operative time, estimated blood loss, postoperative pain, union rate, time to union, functional score, paresthesia, complications, implant removal rate, and complication rate-were recorded.

RESULTS

Incisional or anterior chest wall numbness and intraoperative blood loss were significantly less (p < 0.001) in the nerve-sparing group. The operative time was similar in the two groups. No significant differences were discovered in QuickDASH score, postoperative pain score, union rate, time to union, implant removal rate, complication rate, or revision rate.

CONCLUSIONS

Our study demonstrated that the outcomes of supraclavicular nerve sparing during ORIF with WALANT can reduce postoperative incisional and anterior chest wall numbness and intraoperative blood loss without increasing the operative time or complication rate.

Safe zone of supraclavicular nerve during clavicle fixation and its anatomical variations, a cadaveric study

BACKGROUND

Supraclavicular nerve injury is usually at risk during clavicular fracture fixation. This study aimed to examine the anatomical features and estimate the precise location of supraclavicular nerve branches related to adjacent structural landmarks and to evaluate the differences between sex and side. To highlight the clinical purposes and surgical relevance, this study attempted to define a surgical safe zone that would probably protect the supraclavicular nerve during clavicle fixation.

METHOD

A total of 64 shoulders obtained from 15 female and 17 male adult cadavers were examined, identifying the branching patterns of the supraclavicular nerve, measuring the clavicle length and the course of the supraclavicular nerve referring to the sternoclavicular (SC) and acromioclavicular (AC) joint. Data were categorized by sex and side, and their differences were evaluated using Student T-Test and Mann-Whitney U Test. Clinically relevant predictable safe zones were also statistically analyzed.

RESULT

The results revealed 7 branching patterns of the supraclavicular nerve. The medial and lateral nerve branches formed a shared trunk, and the medial nerve branches separated to form the intermediate branch, i.e., the most frequent pattern (67.19%). The safe zones were determined to be 6.1 mm among both sexes of the SC joint medially, and 0.7 mm among females and 0 mm among males of the AC joint laterally. Surgical incisions between 29.3 to 51.2% and 60.5 to 79.7% of the clavicle length from the SC joint were the safe zones at the midclavicular shaft among both sexes.

CONCLUSION

The findings of this study have provided new insights into the anatomy of the supraclavicular nerve and its variations. It has been revealed that the terminal branches of the nerve consistently pass over the clavicle in a predictable pattern, emphasizing the importance of considering the supraclavicular nerve's safe zones during clinically relevant surgeries. Nevertheless, due to individual anatomical variations, meticulous dissection between these safe zones is necessary to avoid iatrogenic nerve injury among patients.

LEVEL OF EVIDENCE

Basic Science Study, Anatomic Study.

Insertion sites of the muscles attached to the clavicle: a cadaveric study of the clavicle

BACKGROUND

Clavicle fractures are common injuries, especially in young, active individuals. Operative treatment is recommended for completely displaced clavicle shaft fractures, and plate fixation is stronger than the use of intramedullary nails. Few studies have reported on iatrogenic injuries to the muscle attached to the clavicle during fracture surgery. The aim of this study was to clarify the area of the insertion sites of muscles attached to the clavicle in Japanese cadavers using gross anatomy and three-dimensional (3D) analysis. We also aimed to compare the effects of anterior plate templating and superior plate templating on clavicle shaft fractures using 3D images.

METHODS

Thirty-eight clavicles from Japanese cadavers were analyzed. We removed all clavicles to identify the insertion sites and measured the size of the insertion area of each muscle. Three-dimensional templating was performed on both the superior and anterior plates of the clavicle using data obtained from computed tomography. The areas covered by these plates on the muscles attached to the clavicle were compared. Histological examination was performed on four randomly selected specimens.

RESULTS

The sternocleidomastoid muscle was attached proximally and superiorly; the trapezius muscle was attached posteriorly and partly superiorly; and the pectoralis major muscle and deltoid muscles were attached anteriorly and partially superiorly. The non-attachment area was located mainly in the posterosuperior part of the clavicle. It was difficult to distinguish the borders of the periosteum and pectoralis major muscles. The anterior plate covered a significantly broader area (mean 6.94 ± 1.36 cm²) of the muscles attached to the clavicle than did the superior plate (mean 4.11 ± 1.52 cm²) (p < 0.0001). On microscopy, these muscles were inserted directly into the periosteum.

CONCLUSION

Most of the pectoralis major and deltoid muscles were attached anteriorly. The non-attachment area was located mainly from the superior to posterior part of the clavicle midshaft. Both macroscopically and microscopically, the boundaries between the periosteum and these muscles were difficult to demarcate. The anterior plate covered a significantly broader area of the muscles attached to the clavicle than that by the superior plate.

Case Report and Preliminary Exploration: Protection of Supraclavicular Nerve Branches during Internal Fixation of Clavicular Fractures through Preoperative Ultrasound Localization

Introduction

Protecting the supraclavicular nerve during internal fixation of clavicular fractures can reduce numbness in its innervation area after surgery. Previous methods for supraclavicular nerve protection are empirical, time-consuming, and approximate. In this report, we verified the feasibility of using ultrasound for percutaneous localization of the terminal branches of the supraclavicular nerve and the feasibility of an ultrasound-guided skin flap reserve technique for nerve protection.

Case Presentations

A high-frequency linear array probe was used in three cases to trace the supraclavicular nerve from its origin at the superficial cervical plexus on the surface of the clavicle. In the first case, the feasibility of percutaneous ultrasound localization of the terminal branches of the supraclavicular nerve was determined by performing an ultrasound-guided nerve block. In the second case, the feasibility of this method was determined by directly isolating this nerve under direct vision. In the third case, after the ultrasound localization, the nerves were protected by intraoperative skin retention. In the first case, skin anesthesia of the innervation area of the intermediate branch of the supraclavicular nerve was achieved. In the second case, the part of the nerve that crosses the surface of the clavicle was quickly found and successfully protected, and no obvious abnormal skin sensations were noted after the operation. In the third case, there was no abnormal sensation in most of the associated skin except for the innervation area of the lateral branch of the supraclavicular nerve.

Conclusions

The medial and intermediate branches of the supraclavicular nerve could be located over the skin by ultrasound, and this could be helpful in quickly isolating these nerves intraoperatively. Retaining the corresponding skin can protect the function of these nerve branches and effectively reduce the area of skin numbness after surgery.

Incisional paresthesia following clavicle plate fixation: does it matter to patients?

Background

Operative management of clavicle fractures is increasingly common. In the context of explaining the risks and benefits of surgery, understanding the impact of incisional numbness as it relates to the patient experience is key to shared decision making. This study aims to determine the prevalence, extent, and recovery of sensory changes associated with supraclavicular nerve injury after open reduction and plate internal fixation of middle or lateral clavicle shaft fractures.

Methods

Eighty-six patients were identified retrospectively and completed a patient experience survey assessing sensory symptoms, perceived post-operative function, and satisfaction. Correlations between demographic factors and outcomes, as well as subgroup analyses were completed to identify factors impacting patient satisfaction.

Results

Ninety percent of patients experienced sensory changes post-operatively. Numbness was the most common symptom (64%) and complete resolution occurred in 32% of patients over an average of 19 months. Patients who experienced burning were less satisfied overall with the outcome of their surgery whereas those who were informed of the risk of sensory changes pre-operatively were more satisfied overall.

Conclusions

Post-operative sensory disturbance is common. While most patients improve, some symptoms persist in the majority of patients without significant negative effects on satisfaction. Patients should always be advised of the risk of persistent sensory alterations around the surgical site to increase the likelihood of their satisfaction post-operatively.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04770-z.