Definition/Description
Anterior cervical discectomy and fusion (ACDF) is one of the most common surgical procedures performed by neuro and spinal orthopedic surgeons. The most common reason for this procedure is a ruptured cervical disc. Another reason for surgery is stimulation of the irritated nerve root 19 . These burrs can be removed by operating specialists. A discectomy is done to give more space to the blocked nerve (= decompression) and fusion is necessary to stabilize the cervical segment.
Clinically Relevant Anatomy
[3] The cervical spine consists of 7 vertebrae numbered C1-C7. The two upper vertebrae have a unique shape. The atlas (C1) supports the head and provides the possibility to move the head forward and backward (eg nodding “yes”). Axis (C2) allows the head to move the head Landscape (e.g. shake “no”). The remaining five vertebrae have weight-bearing functions. The main function of the cervical spine is to support the head and allow it to move, the most important muscles in this area are 1) M. Sternohyoideus 2) M. Omohyoideus 3) M. Sternothyroideus 4) M. Sternohyoideus 5) M. Sternocleidomastoideus 6) M. Stylohyoideus3 .
Indications for procedure
• Diagnostic tests (MRI CT myelography) showing a herniated or degenerated disc in the neck • Degenerative disease, including herniated disc and spinal stenosis8 • Significant weakness in the hand or arm • Arm pain worse than neck pain • If unwell Treatment or medication does not relieve your neck or arm pain from compression of nerves in your spinal cord • Cervical spondylotic myelopathy13
Outcome Measures
Treatment outcomes after spinal surgery are often measured with the help of patient-reported outcome (PRO) questionnaires. A better ACDF-specific measurement tool is the Patient Reported Outcome Questionnaire (VAS-Neck Pain [NP] VAS-Arm Pain [AP] NDI SF-12 and EQ-5D.) We can also use Anchored-based MCID values were calculated using the North American Spine Society (NASS) Patient Satisfaction Scale as an anchor: 1) Mean Change 2) Minimum Detectable Change (MDC) 3) Difference in Change and 4) Receiver Operating Characteristics (ROC) curve analysis. here Reflects minimal clinically important difference (MCID) clinically meaningful improvement for patients6. SF-36 PCS is the most representative PRO measure. MDC seems to be the most suitable MCID method7.
Medical Management
An incision is made in the front of the spine through the throat area. After the disc is removed, a bone graft is inserted to fuse the bones above and below the disc together. A discectomy literally means removal of a disc in the spine. Discectomy can be performed from the neck anywhere along the spine (cervical spine) to the lower back (lumbar spine). The surgeon accesses the damaged disc from the front (anterior) of the spine through the larynx area. By moving the neck muscles, trachea, and esophagus aside, the discs and bony vertebrae are exposed. Surgery is easier to perform from the front of the neck than from the neck Back (posterior) because the discs can be reached without interfering with the spinal nerves and strong neck muscles. Depending on your specific symptoms, one disc (single layer) or more (multilayer) may be removed. After the disc is removed, the space between the bony vertebrae is empty. To prevent the vertebrae from collapsing and rubbing together, spacer bone grafts are inserted to fill the open disc space. The graft acts as a bridge between the two vertebrae to achieve spinal fusion. The bone graft and vertebrae are held in place with metal plates and screws. The following Surgery As the body begins its natural healing process, new bone cells grow around the graft. After 3 to 6 months, the bone graft should connect the two vertebrae and form one strong bone. Instrumentation and Fusion work together like RC. 1910
Complications
Every surgery has risks; possible complications of ACDF will depend on the competence of the surgeon and the individual risk factors of the patient, eg: smoking, physical condition, diabetes, bone strength of the affected disc, etc…104 The possible complications are :- develop Isolated postoperative dysphagia – postoperative hematoma – symptomatic recurrent laryngeal nerve palsy – inadequate postoperative symptom relief – infection – vertebral artery injury during elective anterior cervical discectomy and C3 to 7 disc fusion9 – internal carotid Venous Thrombosis 11 – hoarse
Regarding postoperative dysphagia, if the surgical level involves C3-C4, the LEO approach (lateral surgical resection of the hyoid muscle) should be chosen. If the C6-C7 of the vertebrae are damaged, a left MEO approach (medial surgical resection to Myohyoid muscle) 5.
You may notice some range of loss of motion after fusion, but this will vary based on preoperative neck mobility and number of fused levels. If only one level is fused, your range of motion may be similar to or better than it was before surgery. You may notice limitations if more than two levels are fused Turn your head and look 20 up and down.
Physical Therapy Management
After surgery Each doctor has his/her own specific guidelines for the recovery process. Hence the protocol is used. Deviations from protocol depend on previous functional level General health of patient equipment Available patient goals Written in prescription etc. It is the therapist’s responsibility to determine the patient’s actual progress within the protocol guidelines, under the direction of the referring physician. The three important components of this therapy are scapular stability, cervical spine stability, and functional activity. [1] [2]
It is important that the patient follows the limits prescribed by the doctor for the first two weeks and then gradually progresses to functional activities that do not place undue stress on the neck area. 16 Treatment includes:
• Promotes cervical range of motion within a pain-free range. • Treats imbalances of overactive upper trapezius and decreased lower trapezius
trap strength.
• Exercises to increase scapular and cervical stability within safe limits. • Pain Relief • Patient Education (Pacing Healing Time Ergonomic Recommendations)17 Once the patient is able to demonstrate adequate stability without prompting for further development and improved exercise progression Stability (coordination) should be considered. 16
Prognosis
Most studies concluded that neck pain, arm pain, and range of motion improved. If we compare with other treatments such as cervical arthroplasty, we can say that patients who received the Mobi-C TDR device for grade 2 symptomatic degenerative disc disease experienced significantly greater NDI scores improved over ACDF patients at every time point, and VAS neck pain scores improved significantly at 6 weeks, 36n, and 12 months postoperatively. The reoperation rate was significantly higher in the ACDF group at 11.4% compared to 3.1% in the TDR group12. when we Looking at the surgical treatment of symptomatic degenerative disc disease at one level of the cervical spine, we can conclude that after 5 years, ProDisc-C patients had a statistically significant reduction in neck pain intensity and frequency14. Comparison of Cervical Disc Replacement and Anterior Cervical Spine Surgery The advantage of discectomy and fusion in the treatment of cervical spondylotic myelopathy is the lower complication rate of arthroplasty13. Zero-contour implants are the best choice for anterior cervical discectomy and fusion. Incidence at early follow-up The incidence of dysphagia was lower and the duration of symptoms was shorter compared to plate cages 15 .
References
[1] Arts M.P. et al., ‘The Netherlands Cervical Kinematics (NECK) Trial. Cost-effectiveness of anterior cervical discectomy with or without interbody fusion and arthroplasty in the treatment of cervical disc herniation; a double-blind randomized multicenter study.’ BMC Musculoskeletal Disorders. 2010, 11:122. (level of evidence: 1B) [2] Peter F., ‘ACDF: Anterior Cervical Discectomy and Fusion.’ 2011 (level of evidence: 5) [3] Michael Schunke, Erik Schulte, Udo Schumacher, Markus Voll, Karl Wesker, Prometheus, Atlas of Anatomy [4] Fountas, K.N. et al. Anterior cervical discectomy and fusion associated complications. Spine. 2007: 32(31): 2310-7. (level of evidence: 2A) [5] Fengbin Y et al., ‘Dysphagia after anterior cervical discectomy and fusion: a prospective study comparing two anterior surgical approaches.’ Eur Spine J. 2013 May;22(5):1147-51. (level of evidence: 1B) [6] Parker SL et al., ‘Assessment of the minimum clinically important difference in pain, disability, and quality of life after anterior cervical discectomy and fusion: clinical article.’ J Neurosurg Spine 2013 Feb;18(2):154-60. (level of evidence: 2B ) [7] Auffinger BM et al., ‘Measuring surgical outcomes in cervical spondylotic myelopathy patients undergoing anterior cervical discectomy and fusion: assessment of minimum clinically important difference.’ PLoS One. 2013 Jun 24;8(6):e67408 (level of evidence: 3B) [8] Goldberg EJ et al., ‘Comparing outcomes of anterior cervical discectomy and fusion in workman’s versus non-workman’s compensation population.’ Spine J. 2002 Nov-Dec;2(6):408-14. (level of evidence: 2B) [9] Gantwerker BR et al., ‘Vertebral artery injury during cervical discectomy and fusion in a patient with bilateral anomalous arteries in the disc space: case report.’ Neurosurgery. 2010 Sep;67(3):E874-5. (level of evidence: 3B) [10] Grigory Goldberg et al. ‘Anterior Cervical discectomy and fusion.’ Operative techniques in Orthopaedics, Volume 13, Issue 3, 2003 July, pages 188-194. (level of evidence: 3A) [11] Karim A et al., ‘Internal jugular venous thrombosis as a complication after an elective anterior cervical discectomy: case report.’ Neurochirurgy 2006 Sep;59(3):E705. (level of evidence: 3B) [12] Davis RJ et al., ‘Cervical total disc replacement with the Mobi-C cervical artificial disc compared with anterior discectomy and fusion for treatment of 2-level symptomatic degenerative disc disease: a prospective, randomized, controlled multicenter clinical trial: clinical article.’ J Neurosurg Spine. 2013 Nov;19(5):532-45. (level of evidence: 1B) [13] Ding C et al., ‘Comparison of cervical disc arthroplasty with anterior cervical discectomy and fusion for the treatment of cervical spondylotic myelopathy.’ Acta Orthop Belg. 2013 Jun;79(3):338-46. (level of evidence: 2B) [14] Zigler JE et al., ‘ProDisc-C and anterior cervical discectomy and fusion as surgical treatment for single-level cervical symptomatic degenerative disc disease: five-year results of a Food and Drug Administration study.’ Spine (Phila Pa 1976) 2013 Feb 1;38(3):203-9. (level of evidence: 1B) [15] Miao J et al., ‘Early follow-up outcomes of a new zero-profile implant used in anterior cervical discectomy and fusion.’ J Spinal Disord Tech. 2013 Jul;26(5):E193-7. (level of evidence: 1B) [16] Issada Thongtrangan, MD, rehabilitation department, Cervical Fusion Protocol (level of evidence: 5) [17] RNOH; physiotherapy April 2012. Review date 2014, In association with the UCL Institute of Orthopaedics and Musculoskeletal Science, Rehabilitation guidelines for patients undergoing spinal surgery. (Level of evidence: 5) [18] Kamiah A. Walker; Reviewed by Jason M. Highsmith, MD, Physical Therapy to Relieve Neck Pain (level of evidence: 5) [19] Portnoy HD. Anterior cervical discectomy and fusion. Surg neurol 2001; 56: 178-80 (level of evidence: 3A) [20] Watters et al. Anterior Cervical Discectomy With and Without Fusions Results, Complications, and long-term follow-up, Spine, 1994 (level of evidence: 2B)
