Please assess the completion status of the following clinical trial:

Trial Title: Ultrasound-assisted Versus Conventional Landmark-guided Paramedian Spinal Anesthesia in Elderly Patients

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: SINGLE
- Phase: None
- Number of Arms: 2.0

Eligibility Criteria:
Inclusion Criteria:~* Elderly patients (age≥60 years) scheduled to undergoing elective orthopedic surgery under spinal anesthesia~* Patients with ASA physical status classification I, II, III~Exclusion Criteria:~* Patients with contraindication to spinal anesthesia (coagulopathy, local infection, allergy to local anesthetic)~* Patients with morbid cardiac diseases~* Pregnancy~* Patients with previous history of lumbar spine surgery

- Gender: ALL
- Minimum Age: 60 Years
- Maximum Age: None
- Healthy Volunteers: f

Study Arms:
- Ultrasound-assisted (Type: EXPERIMENTAL): Ultrasound-assisted paramedian technique spinal anesthesia will be performed. A Preprocedural ultrasound scan will be performed for skin marking of entry site of spinal needle. Spinal anesthesia will be performed via paramedian approach using the skin marking site as entry point. 0.5% heavy bupivacaine will be administered into intrathecal space.
- Landmark-guided (Type: ACTIVE_COMPARATOR): In these patients, spinal anesthesia will be performed via paramedian approach using conventional landmark palpation technique. Landmark-guided paramedian technique spinal anesthesia will be performed. 0.5% heavy bupivacaine will be administered into intrathecal space.

Based on this trial design, predict the completion outcome and termination type (if applicable).